AMERICAN MIDSTREAM PARTNERS, LP, 10-K filed on 3/7/2016
Annual Report
Document and Entity Information (USD $)
12 Months Ended
Dec. 31, 2015
Jun. 30, 2015
Mar. 4, 2016
Limited Partner Common Units
Mar. 4, 2016
Series A
Entity Registrant Name
American Midstream Partners, LP 
 
 
 
Entity Central Index Key
0001513965 
 
 
 
Document Type
10-K 
 
 
 
Document Period End Date
Dec. 31, 2015 
 
 
 
Amendment Flag
false 
 
 
 
Document Fiscal Year Focus
2015 
 
 
 
Document Fiscal Period Focus
FY 
 
 
 
Current Fiscal Year End Date
--12-31 
 
 
 
Entity Well-known Seasoned Issuer
No 
 
 
 
Entity Voluntary Filers
No 
 
 
 
Entity Current Reporting Status
Yes 
 
 
 
Entity Filer Category
Accelerated Filer 
 
 
 
Entity Public Float
 
$ 354,233,679 
 
 
Entity Common Stock, Shares Outstanding
 
 
30,889,659 
9,499,370 
Consolidated Balance Sheets (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2015
Dec. 31, 2014
Current assets
 
 
Cash and cash equivalents
$ 0 
$ 499 
Accounts receivable
3,181 
4,924 
Unbilled revenue
15,559 
24,619 
Risk management assets
365 
688 
Other current assets
10,094 
15,554 
Total current assets
29,199 
46,284 
Property, plant and equipment, net
648,013 
582,182 
Goodwill
16,300 
142,236 
Intangible assets, net
100,965 
106,306 
Investment in unconsolidated affiliates
82,301 
22,252 
Other assets, net
14,556 
14,298 
Total assets
891,296 
913,558 
Current liabilities
 
 
Accounts payable
4,667 
20,326 
Accrued gas purchases
7,281 
14,326 
Accrued expenses and other current liabilities
25,035 
25,800 
Current portion of long-term debt
2,338 
2,908 
Risk management liabilities
0 
215 
Total current liabilities
39,321 
63,575 
Asset Retirement Obligations, Noncurrent
28,549 
34,645 
Other liabilities
1,001 
126 
Long-term debt
525,100 
372,950 
Deferred tax liability
5,826 
5,113 
Total liabilities
599,797 
476,409 
Commitments and contingencies (see Note 19)
   
   
Series A convertible preferred units (9,210 thousand and 5,745 thousand units issued and outstanding as of December 31, 2015 and December 31, 2014, respectively)
169,712 
107,965 
Equity and partners' capital
 
 
General Partner Interest (536 thousand and 392 thousand units issued and outstanding as of December 31, 2015 and December 31, 2014, respectively)
(104,853)
(2,450)
Accumulated other comprehensive income (loss)
40 
2 
Total partners' capital
117,257 
324,467 
Noncontrolling interests
4,530 
4,717 
Total equity and partners' capital
121,787 
329,184 
Total liabilities, equity and partners' capital
891,296 
913,558 
Limited Partner Common Units [Member]
 
 
Equity and partners' capital
 
 
Limited Partners' Capital Account
188,477 
294,695 
Limited Partner Series B Convertible Units [Member]
 
 
Equity and partners' capital
 
 
Limited Partners' Capital Account
$ 33,593 
$ 32,220 
Consolidated Balance Sheets (Parenthetical)
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
General partners' interest units issued
536,000 
392,000 
185,000 
General partners' interest units outstanding
536,000 
392,000 
185,000 
Limited partners, units issued
30,427,000 
22,670,000 
7,414,000 
Limited partners, units outstanding
30,427,000 
22,670,000 
7,414,000 
Series A
 
 
 
Preferred units issued
9,210,000 
5,745,000 
5,279,000 
Preferred units outstanding
9,210,000 
5,745,000 
5,279,000 
Series B
 
 
 
Preferred units issued
1,350,000 
1,255,000 
0 
Preferred units outstanding
1,350,000 
1,255,000 
0 
Consolidated Statements of Operations (USD $)
Share data in Thousands, except Per Share data, unless otherwise specified
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Revenue
$ 235,034,000 
$ 307,309,000 
$ 294,051,000 
Gain (loss) on commodity derivatives, net
1,324,000 
1,091,000 
28,000 
Total revenue
236,358,000 
308,400,000 
294,079,000 
Operating expenses:
 
 
 
Purchases of natural gas, NGLs and condensate
105,883,000 
197,952,000 
215,053,000 
Direct operating expenses
59,549,000 
45,702,000 
32,236,000 
Selling, general and administrative expenses
27,232,000 
23,103,000 
19,079,000 
Equity compensation expense
3,774,000 
1,536,000 
2,094,000 
Depreciation, amortization and accretion expense
38,014,000 
28,832,000 
30,002,000 
Total operating expenses
234,452,000 
297,125,000 
298,464,000 
Gain (loss) on involuntary conversion of property, plant and equipment
0 
0 
343,000 
Gain (loss) on sale of assets, net
(3,011,000)
(122,000)
0 
Loss on impairment of property, plant and equipment
0 
(99,892,000)
(18,155,000)
Goodwill, Impairment Loss
(118,592,000)
0 
0 
Operating income (loss)
(119,697,000)
(88,739,000)
(22,197,000)
Other income (expense):
 
 
 
Interest expense
(14,745,000)
(7,577,000)
(9,291,000)
Other income (expense)
0 
(670,000)
0 
Earnings in unconsolidated affiliates
8,201,000 
348,000 
0 
Net income (loss) before income tax (expense) benefit
(126,241,000)
(96,638,000)
(31,488,000)
Income tax (expense) benefit
(1,134,000)
(557,000)
495,000 
Net income (loss) from continuing operations
(127,375,000)
(97,195,000)
(30,993,000)
Discontinued operations:
 
 
 
Income (loss) from discontinued operations, net of tax
(80,000)
(611,000)
(2,413,000)
Net income (loss)
(127,455,000)
(97,806,000)
(33,406,000)
Net income (loss) attributable to noncontrolling interests
(25,000)
(214,000)
(633,000)
Net income (loss) attributable to the Partnership
(127,480,000)
(98,020,000)
(34,039,000)
Distribution declared per common unit (a)
$ 1.89 
$ 1.85 
$ 1.75 
Basic and diluted:
 
 
 
Income (Loss) from Continuing Operations, Per Outstanding Limited Partnership Unit, Basic
$ (6.00)
$ (8.54)
$ (7.15)
Limited Partners' net income (loss) from discontinued operations per unit (basic and diluted)
$ 0.00 
$ (0.04)
$ (0.27)
Limited partners’ net income (loss) per unit (basic and diluted)
$ (6.00)
$ (8.58)
$ (7.42)
Weighted average number of common units outstanding:
 
 
 
Basic and diluted
24,983 
13,472 
7,525 
Total Partners Capital
 
 
 
Discontinued operations:
 
 
 
Net income (loss) attributable to the Partnership
(127,480,000)
(98,020,000)
(34,039,000)
General Partner Interest
 
 
 
Discontinued operations:
 
 
 
General Partner's Interest in net income (loss)
(1,645,000)
(1,279,000)
(1,405,000)
Limited Partner [Member]
 
 
 
Discontinued operations:
 
 
 
Limited Partners' Interest in net income (loss)
$ (125,835,000)
$ (96,741,000)
$ (32,634,000)
Consolidated Statements of Comprehensive Income (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
 
 
 
Net income (loss)
$ (127,455)
$ (97,806)
$ (33,406)
Unrealized gain (loss) on postretirement benefit plan assets and liabilities
38 
(102)
(247)
Comprehensive income (loss)
(127,417)
(97,908)
(33,653)
Net income (loss) attributable to noncontrolling interests
(25)
(214)
(633)
Comprehensive income (loss) attributable to Partnership
$ (127,442)
$ (98,122)
$ (34,286)
Consolidated Statements of Changes in Partners' Capital and Noncontrolling Interest (USD $)
Total
General Partner Interest
Limited Partner Interest
Series B
Accumulated Other Comprehensive Income
Total Partners Capital
Blackwater [Member]
Noncontrolling Interest
Blackwater [Member]
Blackwater [Member]
General Partner Interest
Blackwater [Member]
Limited Partner Interest
Blackwater [Member]
Total Partners Capital
Series B
Series B
Series B
Accumulated Other Comprehensive Income
Series B
Total Partners Capital
Series B
Noncontrolling Interest
Beginning Balance at Dec. 31, 2012
 
$ 548,000 
$ 79,266,000 
 
$ 351,000 
$ 80,165,000 
 
$ 7,438,000 
 
 
 
 
 
 
 
 
 
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests
 
37,000 
1,993,000 
 
 
2,030,000 
 
2,782,000 
 
 
 
 
 
 
 
 
 
General Partner's Interest in net income (loss)
 
(1,405,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Limited Partners' Interest in net income (loss)
 
 
(32,634,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Net income (loss)
(34,039,000)
 
 
 
 
(34,039,000)
 
633,000 
 
 
 
 
 
 
 
 
 
Issuance of common units, net of offering costs
54,900,000 
 
54,853,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Unit holder contributions
 
12,500,000 
 
 
 
12,500,000 
22,696,000 
 
 
 
 
22,696,000 
 
 
 
 
 
Unitholder distributions
(16,120,000)
(623,000)
(21,628,000)
 
 
(22,251,000)
 
 
(27,650,000)
(30,702,000)
 
 
0 
 
 
 
 
General Partner Noncash Distributions
 
 
 
 
 
 
 
 
 
 
3,052,000 
 
 
 
 
 
 
Fair value of Series A Units in excess of High Point System net assets received
(15,612,000)
312,000 
15,300,000 
 
 
15,612,000 
 
 
 
 
 
 
 
 
 
 
 
Net distributions to noncontrolling interest owners
 
 
 
 
 
 
 
(661,000)
 
 
 
 
 
 
 
 
 
LTIP vesting
 
(2,067,000)
2,067,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Tax netting repurchase
630,000 
 
(630,000)
 
 
(630,000)
 
 
 
 
 
 
 
 
 
 
 
Unit based compensation
 
2,024,000 
 
 
 
2,024,000 
 
 
 
 
 
 
 
 
 
 
 
Other comprehensive income (loss)
(247,000)
 
 
 
(247,000)
(247,000)
 
 
 
 
 
 
 
 
 
 
 
Ending Balance at Dec. 31, 2013
 
2,696,000 
71,039,000 
 
104,000 
73,839,000 
 
4,628,000 
 
 
 
 
 
 
 
 
 
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests
 
0 
21,000 
 
 
21,000 
 
189,000 
 
 
 
 
 
 
 
 
 
General Partner's Interest in net income (loss)
 
(1,279,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Limited Partners' Interest in net income (loss)
 
 
(96,741,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Net income (loss)
(98,020,000)
 
 
 
 
(98,020,000)
 
 
 
 
 
 
 
 
 
 
 
Net Income (loss) attributable to noncontrolling interests
 
 
 
 
 
 
 
214,000 
 
 
 
 
 
 
 
 
 
Issuance of common units, net of offering costs
119,300,000 
 
351,551,000 
 
 
351,551,000 
 
 
 
 
 
 
 
 
 
 
 
Issuance of Series B Units
 
 
 
 
 
 
 
 
 
 
 
 
 
32,220,000 
 
 
 
Unit holder contributions
 
5,678,000 
0 
 
0 
5,678,000 
 
 
 
 
 
 
 
 
 
 
 
Unitholder distributions
(28,009,000)
(2,913,000)
(39,150,000)
 
 
(42,063,000)
 
 
 
 
 
 
(2,220,000)
 
 
 
 
Fair value of Series A Units in excess of High Point System net assets received
0 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Issuance and exercise of warrants
 
(7,164,000)
7,164,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Net distributions to noncontrolling interest owners
 
0 
0 
 
0 
0 
 
(314,000)
 
 
 
 
 
 
 
 
 
LTIP vesting
 
(824,000)
1,067,000 
 
 
243,000 
 
 
 
 
 
 
 
 
 
 
 
Tax netting repurchase
256,000 
 
256,000 
 
 
256,000 
 
 
 
 
 
 
 
 
 
 
 
Unit based compensation
 
1,356,000 
 
 
 
1,356,000 
 
 
 
 
 
 
 
 
 
 
 
Other comprehensive income (loss)
(102,000)
 
 
 
(102,000)
(102,000)
 
 
 
 
 
 
 
 
 
 
 
Ending Balance at Dec. 31, 2014
324,467,000 
(2,450,000)
294,695,000 
32,220,000 
2,000 
324,467,000 
 
4,717,000 
 
 
 
 
 
 
 
 
 
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests
 
0 
20,000 
0 
0 
20,000 
 
172,000 
 
 
 
 
 
 
 
 
 
General Partner's Interest in net income (loss)
 
(1,645,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Limited Partners' Interest in net income (loss)
 
 
(125,835,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Net income (loss)
(127,480,000)
 
 
 
 
(127,480,000)
 
25,000 
 
 
 
 
 
 
 
 
 
Issuance of common units, net of offering costs
 
0 
82,421,000 
0 
0 
 
 
0 
 
 
 
 
 
 
 
 
 
Issuance of Series B Units
 
 
0 
 
 
 
 
 
 
 
 
 
 
1,373,000 
0 
1,373,000 
0 
Unit holder contributions
 
1,996,000 
0 
0 
 
1,996,000 
 
0 
 
 
 
 
 
 
 
 
 
Unitholder distributions
(53,386,000)
(7,023,000)
(64,714,000)
 
 
(71,737,000)
500,000 
 
 
 
 
 
(1,373,000)
 
 
 
 
Partners Capital Account Distributions, Delta House
 
(96,297,000)
 
 
 
 
27,700,000 
 
 
 
 
 
 
 
 
 
 
Fair value of Series A Units in excess of High Point System net assets received
0 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Net distributions to noncontrolling interest owners
 
0 
0 
0 
0 
0 
 
(40,000)
 
 
 
 
 
 
 
 
 
LTIP vesting
 
(2,490,000)
2,686,000 
 
 
196,000 
 
 
 
 
 
 
 
 
 
 
 
Tax netting repurchase
756,000 
 
(756,000)
0 
 
(756,000)
 
 
 
 
 
 
 
 
 
 
 
Unit based compensation
 
3,056,000 
0 
0 
0 
3,056,000 
 
0 
 
 
 
 
 
 
 
 
 
Other comprehensive income (loss)
38,000 
 
 
 
38,000 
38,000 
 
 
 
 
 
 
 
 
 
 
 
Ending Balance at Dec. 31, 2015
$ 117,257,000 
$ (104,853,000)
$ 188,477,000 
$ 33,593,000 
$ 40,000 
$ 117,257,000 
 
$ 4,530,000 
 
 
 
 
 
 
 
 
 
Consolidated Statements of Cash Flows (USD $)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2015
Blackwater [Member]
Dec. 31, 2014
Blackwater [Member]
Dec. 31, 2013
Blackwater [Member]
Dec. 31, 2015
ArcLight [Member]
Dec. 31, 2014
ArcLight [Member]
Dec. 31, 2013
ArcLight [Member]
Dec. 31, 2015
Noncontrolling Interest
Dec. 31, 2014
Noncontrolling Interest
Dec. 31, 2013
Noncontrolling Interest
Dec. 31, 2015
Series A
Dec. 31, 2014
Series A
Cash flows from operating activities
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Net income (loss)
$ (127,455,000)
$ (97,806,000)
$ (33,406,000)
 
 
 
 
 
 
 
 
 
 
 
Depreciation, Depletion and Amortization
38,014,000 
28,832,000 
30,002,000 
 
 
 
 
 
 
 
 
 
 
 
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Depreciation, amortization and accretion expense
 
28,832,000 
29,999,000 
 
 
 
 
 
 
 
 
 
 
 
Amortization of deferred financing costs
1,482,000 
2,212,000 
1,334,000 
 
 
 
 
 
 
 
 
 
 
 
Amortization of weather derivative premium
912,000 
1,035,000 
662,000 
 
 
 
 
 
 
 
 
 
 
 
Unrealized (gain) loss on derivative contracts, net
71,000 
(595,000)
1,505,000 
 
 
 
 
 
 
 
 
 
 
 
Non-cash compensation
3,863,000 
1,626,000 
2,094,000 
 
 
 
 
 
 
 
 
 
 
 
Postretirement expense (benefit)
(14,000)
(45,000)
(73,000)
 
 
 
 
 
 
 
 
 
 
 
(Gain) loss on involuntary conversion of property, plant and equipment
0 
0 
(343,000)
 
 
 
 
 
 
 
 
 
 
 
(Gain) loss on sale of assets, net
3,161,000 
207,000 
75,000 
 
 
 
 
 
 
 
 
 
 
 
Loss on impairment of property, plant and equipment
0 
99,892,000 
18,155,000 
 
 
 
 
 
 
 
 
 
 
 
Loss on impairment of noncurrent assets held for sale
0 
673,000 
2,400,000 
 
 
 
 
 
 
 
 
 
 
 
Loss on impairment of goodwill
118,592,000 
0 
0 
 
 
 
 
 
 
 
 
 
 
 
Earnings in unconsolidated affiliates
(8,201,000)
(348,000)
0 
 
 
 
 
 
 
 
 
 
 
 
Distributions from unconsolidated affiliates
8,201,000 
348,000 
0 
 
 
 
 
 
 
 
 
 
 
 
Deferred tax expense (benefit)
953,000 
213,000 
(847,000)
 
 
 
 
 
 
 
 
 
 
 
Changes in operating assets and liabilities, net of effects of assets acquired and liabilities assumed:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Accounts receivable
1,743,000 
13,067,000 
(790,000)
 
 
 
 
 
 
 
 
 
 
 
Unbilled revenue
9,060,000 
2,272,000 
(226,000)
 
 
 
 
 
 
 
 
 
 
 
Risk management assets and liabilities
(875,000)
(809,000)
(1,147,000)
 
 
 
 
 
 
 
 
 
 
 
Other current assets
(962,000)
(7,533,000)
(1,614,000)
 
 
 
 
 
 
 
 
 
 
 
Other assets, net
(522,000)
6,049,000 
(823,000)
 
 
 
 
 
 
 
 
 
 
 
Accounts payable
(3,643,000)
(12,026,000)
(845,000)
 
 
 
 
 
 
 
 
 
 
 
Accrued gas purchases
(7,045,000)
(5,540,000)
462,000 
 
 
 
 
 
 
 
 
 
 
 
Accrued expenses and other current liabilities
2,857,000 
(9,149,000)
769,000 
 
 
 
 
 
 
 
 
 
 
 
Asset retirement obligations
(90,000)
(1,030,000)
0 
 
 
 
 
 
 
 
 
 
 
 
Other liabilities
835,000 
(67,000)
(118,000)
 
 
 
 
 
 
 
 
 
 
 
Net cash provided by operating activities
40,937,000 
21,478,000 
17,223,000 
 
 
 
 
 
 
 
 
 
 
 
Net cash provided by operating activities
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Cost of acquisitions, net of cash acquired and settlements
(7,383,000)
362,316,000 
0 
 
 
 
 
 
 
 
 
 
 
 
Additions to property, plant and equipment
(130,549,000)
(96,998,000)
(27,196,000)
 
 
 
 
 
 
 
 
 
 
 
Proceeds from disposal of property, plant and equipment
4,813,000 
6,323,000 
500,000 
 
 
 
 
 
 
 
 
 
 
 
Insurance proceeds from involuntary conversion of property, plant and equipment
0 
0 
482,000 
 
 
 
 
 
 
 
 
 
 
 
Investment in unconsolidated affiliates
(71,597,000)
(12,000,000)
0 
 
 
 
 
 
 
 
 
 
 
 
Proceeds from equity method investment, return of capital
12,367,000 
1,632,000 
0 
 
 
 
 
 
 
 
 
 
 
 
Restricted cash
6,475,000 
(8,511,000)
(2,000,000)
 
 
 
 
 
 
 
 
 
 
 
Net cash used in investing activities
(171,108,000)
(471,870,000)
(28,214,000)
 
 
 
 
 
 
 
 
 
 
 
Cash flows from financing activities
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Proceeds from issuance of common units to public, net of offering costs
82,488,000 
204,255,000 
54,853,000 
 
 
 
 
 
 
 
 
 
 
 
Unitholder contributions
1,905,000 
5,588,000 
13,075,000 
 
 
 
 
 
 
 
 
 
 
 
Payments of Distributions to Affiliates
(53,386,000)
(28,009,000)
(16,120,000)
 
 
 
 
 
 
 
 
 
 
 
Issuance of Units
44,768,000 
0 
14,393,000 
 
 
 
 
 
 
 
 
 
 
 
Unitholder distributions for common control transactions
 
 
 
(96,297,000)
0 
(27,650,000)
 
 
 
 
 
 
 
 
Acquisition of noncontrolling interests
(74,000)
(8,000)
(752,000)
 
 
 
 
 
 
 
 
 
 
 
Net distributions to noncontrolling interests
 
 
 
 
 
 
 
 
 
(40,000)
(314,000)
(661,000)
 
 
LTIP tax netting unit repurchase
(756,000)
(256,000)
(630,000)
 
 
 
 
 
 
 
 
 
 
 
Deferred financing costs
(2,238,000)
(3,841,000)
(2,113,000)
 
 
 
 
 
 
 
 
 
 
 
Payments on other debt
(3,557,000)
(2,589,000)
(2,640,000)
 
 
 
 
 
 
 
 
 
 
 
Borrowings on other debt
4,709,000 
3,449,000 
3,795,000 
 
 
 
 
 
 
 
 
 
 
 
Payments on loan to affiliate
0 
0 
(20,000,000)
 
 
 
 
 
 
 
 
 
 
 
Payments on bank loans
0 
0 
(34,730,000)
 
 
 
 
 
 
 
 
 
 
 
Borrowings on bank loans
0 
0 
27,546,000 
 
 
 
 
 
 
 
 
 
 
 
Payments on long-term debt
(189,150,000)
(250,870,000)
(131,571,000)
 
 
 
 
 
 
 
 
 
 
 
Borrowings on long-term debt
341,300,000 
493,085,000 
134,021,000 
 
 
 
 
 
 
 
 
 
 
 
Net cash provided by financing activities
129,672,000 
450,490,000 
10,816,000 
 
 
 
 
 
 
 
 
 
 
 
Net increase (decrease) in cash and cash equivalents
(499,000)
98,000 
(175,000)
 
 
 
 
 
 
 
 
 
 
 
Cash and cash equivalents
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Beginning of period
499,000 
401,000 
576,000 
 
 
 
 
 
 
 
 
 
 
 
End of period
0 
499,000 
401,000 
 
 
 
 
 
 
 
 
 
 
 
Supplemental cash flow information
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Interest payments, net
12,013,000 
6,726,000 
6,416,000 
 
 
 
 
 
 
 
 
 
 
 
Supplemental non-cash information
 
 
 
 
 
 
 
 
 
 
 
 
 
 
(Decrease) increase in accrued property, plant and equipment
25,637,000 
(31,390,000)
5,181,000 
 
 
 
 
 
 
 
 
 
 
 
Noncash or Part Noncash Acquisition, Net Nonmonetary Assets Acquired (Liabilities Assumed)
 
 
 
0 
0 
22,121,000 
0 
0 
59,995,000 
 
 
 
 
 
Fair value of Series A Units in excess of net assets received
0 
0 
15,612,000 
 
 
 
 
 
 
 
 
 
 
 
Accrued and paid-in-kind unitholder distribution for Series A Units
 
 
4,811,000 
 
 
 
 
 
 
 
 
 
16,978,000 
13,154,000 
Dividends, Paid-in-kind
 
 
$ 0 
 
 
 
 
 
 
 
 
 
$ 1,373,000 
$ 2,220,000 
Organization and Basis of Presentation
Organization and Basis of Presentation
Organization, Basis of Presentation and Summary of Significant Accounting Policies

General

American Midstream Partners, LP (the "Partnership"), was formed on August 20, 2009 as a Delaware limited partnership for the purpose of operating, developing and acquiring a diversified portfolio of midstream energy assets. The Partnership's general partner, American Midstream GP, LLC (the "General Partner"), is 95% owned by High Point Infrastructure Partners, LLC ("HPIP") and 5% owned by AIM Midstream Holdings, LLC. We hold our assets primarily in a number of wholly owned limited liability companies, two limited partnerships and a corporation. Our capital accounts consist of notional general partner units and limited partner interests.

Nature of business

We are engaged in the business of gathering, treating, processing, and transporting natural gas; gathering, transporting, storing, treating and fractionating NGLs; gathering, storing and transporting crude oil and condensates; and storing specialty chemical products, all through our ownership and operation of twelve gathering systems, five processing facilities, three fractionation facilities, three marine terminal sites, three interstate pipelines, five intrastate pipelines and one crude oil pipeline. We also own a 66.7% non-operated interest in Main Pass Oil Gathering Company ("MPOG"), a crude oil gathering and processing system; a 50% undivided, non-operated interest in the Burns Point Plant, a natural gas processing plant; a 46% non-operated interest in Mesquite, an off-spec condensate fractionation project; and a 12.9% non-operated indirect interest in the Delta House floating production system and related pipeline infrastructure ("Delta House"). Our primary assets, which are strategically located in Alabama, Georgia, Louisiana, Mississippi, North Dakota, Tennessee, Texas and the Gulf of Mexico, provide critical infrastructure that links producers of natural gas, crude oil, NGLs, condensate and specialty chemicals to numerous intermediate and end-use markets. We currently operate more than 3,000 miles of pipelines that gather and transport over 1 Bcf/d of natural gas and operate approximately 1.8 million barrels of storage capacity across three marine terminal sites.

Basis of presentation

We have prepared the accompanying consolidated financial statements in accordance with accounting principles generally accepted in the United States of America ("GAAP").

The results of operations for acquisitions accounted for as business combinations have been included in the consolidated financial statements since their respective acquisition dates. See Note 2 "Acquisitions and Divestitures" for further information.

Transactions Between Entities Under Common Control
 
We may enter into transactions with our General Partner and affiliates whereby we receive a contribution of midstream assets or subsidiaries in exchange for consideration from the Partnership. We account for the net assets received using the historical book value of the asset or subsidiary being contributed or transferred as these are transactions between entities under common control. Our historical financial statements may be revised to include the results attributable to the assets contributed from our General Partner as if we owned such assets for all periods presented by the Partnership since either the change in control of our General Partner, effective April 15, 2013 or later.

Consolidation policy

The accompanying consolidated financial statements include accounts of American Midstream Partners, LP, and its controlled subsidiaries. All significant inter-company accounts and transactions have been eliminated in the preparation of the accompanying consolidated financial statements.

Investment in Unconsolidated Affiliates

Equity investments in which the Partnership exercises significant influence, but does not control and is not the primary beneficiary, are accounted for using the equity method and are reported in Investment in unconsolidated affiliates in the accompanying consolidated balance sheets.

The Partnership believes the equity method is an appropriate means for it to recognize increases or decreases measured by GAAP in the economic resources underlying the investments. Regular evaluation of these investments is appropriate to evaluate any potential need for impairment. The Partnership uses evidence of a loss in value to identify if an investment has declined in value, other than a temporary decline.

The Partnership accounts for its 66.7% non-operated interest in MPOG, its 46.0% non-operated interest in Mesquite and its 12.9% non-operated indirect interest in Delta House under the equity method.

Use of estimates

When preparing consolidated financial statements in conformity with GAAP, management must make estimates and assumptions based on information available at the time. These estimates and assumptions affect the reported amounts of assets, liabilities, revenues and expenses, as well as the disclosures of contingent assets and liabilities as of the date of the financial statements. Estimates and assumptions are based on information available at the time such estimates and assumptions are made. Adjustments made with respect to the use of these estimates and assumptions often relate to information not previously available. Uncertainties with respect to such estimates and assumptions are inherent in the preparation of financial statements. Estimates and assumptions are used in, among other things, i) estimating unbilled revenues, product purchases and operating and general and administrative costs, ii) developing fair value assumptions, including estimates of future cash flows and discount rates, iii) analyzing long-lived assets, goodwill and intangible assets for possible impairment, iv) estimating the useful lives of assets and v) determining amounts to accrue for contingencies, guarantees and indemnifications. Actual results, therefore, could differ materially from estimated amounts.

Cash and cash equivalents

We consider all highly liquid investments with an original maturity of three months or less at the date of purchase to be cash equivalents. The carrying value of cash and cash equivalents approximates fair value because of the short term to maturity of these investments.

Allowance for doubtful accounts

We establish provisions for losses on accounts receivable when we determine that we will not collect all or part of an outstanding balance. Collectability is reviewed regularly and an allowance is established or adjusted, as necessary, using the specific identification method. As of December 31, 2015 and 2014, the Partnership recorded no allowances for losses on accounts receivable.

Operational balancing agreements and natural gas imbalances

To facilitate deliveries of natural gas and provide for operational flexibility, we have operational balancing agreements in place with other interconnecting pipelines. These agreements ensure that the volume of natural gas a shipper schedules for transportation between two interconnecting pipelines equals the volume actually delivered. If natural gas moves between pipelines in volumes that are more or less than the volumes the shipper previously scheduled, a natural gas imbalance is created. The imbalances are settled through periodic cash payments or repaid in-kind through future receipt or delivery of natural gas. Natural gas imbalances are recorded as gas imbalances and classified within Other current assets or Other current liabilities on our consolidated balance sheets at cost which approximates fair value.

Derivative financial instruments

Our net income (loss) and cash flows are subject to volatility stemming from changes in interest rates on our variable rate debt, commodity prices and fractionation margins (the relative difference between the price we receive from NGL sales and the corresponding cost of natural gas purchases). In an effort to manage the risks to unitholders, we use a variety of derivative financial instruments including swaps, collars and interest rate caps to create offsetting positions to specific commodity or interest rate exposures. In accordance with the authoritative accounting guidance, we record all derivative financial instruments in our consolidated balance sheets at fair value as current and long-term assets or liabilities on a net basis by counterparty. We record changes in the fair value of our derivative financial instruments in our consolidated statements of operations as follows:

•
Commodity-based derivatives: "Total revenue"
•
Corporate interest rate derivatives: "Interest expense"

Our formal hedging program provides a control structure and governance for our hedging activities specific to identified risks and time periods, which are subject to the approval and monitoring by the Board of Directors of our General Partner. We employ derivative financial instruments in connection with an underlying asset, liability or anticipated transaction, and we do not use derivative financial instruments for speculative or trading purposes.

The price assumptions we use to value our derivative financial instruments can affect net income (loss) for each period. We use published market price information where available, or quotations from over-the-counter, or OTC, market makers to find executable bids and offers. The valuations also reflect the potential impact of conditions, including credit risk of our counterparties. The amounts reported in our consolidated financial statements change quarterly as these valuations are revised to reflect actual results, changes in market conditions or other factors, many of which are beyond our control.

Fair value measurements

We apply the authoritative accounting provisions for measuring fair value of our derivative instruments and disclosures associated with our outstanding indebtedness. We define fair value as an exit price representing the expected amount we would receive when selling an asset or pay to transfer a liability in an orderly transaction with market participants at the measurement date.

We use various assumptions and methods in estimating the fair values of our financial instruments. The carrying amounts of cash and cash equivalents, accounts receivable and accounts payable approximated their fair value due to the short-term maturity of these instruments. The carrying amount of our various credit facilities approximate fair value, because the interest rates on these facilities are variable.

We employ a hierarchy which prioritizes the inputs we use to measure recurring fair value into three distinct categories based upon whether such inputs are observable in active markets or unobservable. We classify assets and liabilities in their entirety based on the lowest level of input that is significant to the fair value measurement. Our methodology for categorizing assets and liabilities that are measured at fair value pursuant to this hierarchy gives the highest priority to unadjusted quoted prices in active markets and the lowest level to unobservable inputs as outlined below:

•
Level 1 – Inputs represent unadjusted quoted prices in active markets for identical assets or liabilities;
•
Level 2 – Inputs include quoted prices for similar assets and liabilities in active markets that are either directly or indirectly observable; and
•
Level 3 – Inputs are unobservable and considered significant to fair value measurement.

We utilize a mid-market pricing convention, or the "market approach," for valuation for assigning fair value to our derivative assets and liabilities. Our credit exposure for over-the-counter derivatives is directly with our counterparty and continues until the maturity or termination of the contracts. As appropriate, valuations are adjusted for various factors such as credit and liquidity considerations.

Property, plant and equipment

We capitalize expenditures related to property, plant and equipment that have a useful life greater than one year for assets purchased or constructed; existing assets that are replaced, improved, or the useful lives of which have been extended; and all land, regardless of cost. Maintenance and repair costs, including any planned major maintenance activities, are expensed as incurred.

We record property, plant, and equipment at its original cost, which we depreciate on a straight-line basis over its estimated useful life. Our determination of the useful lives of property, plant and equipment requires us to make various assumptions, including the supply of and demand for hydrocarbons in the markets served by our assets, normal wear and tear of the facilities, and the extent and frequency of maintenance programs. We record depreciation using the group method of depreciation, which is commonly used by pipelines, utilities and similar assets.

We classify long-lived assets to be disposed of through sales that meet specific criteria as held for sale. We cease depreciating those assets effective on the date the asset is classified as held for sale. We record those assets at the lower of their carrying value or the estimated fair value less the cost to sell. Until the assets are disposed of, an estimate of the fair value is re-determined when related events or circumstances change.

Impairment of long lived Assets

We evaluate the recoverability of our property, plant and equipment and intangible assets with definite lives when events or circumstances indicate we may not recover the carrying amount of the assets. We continually monitor our operations, the market, and business environment to identify indicators that could suggest an asset or asset group may not be recoverable. We evaluate the asset or asset group for recoverability by estimating the undiscounted future cash flows expected to be derived from their use and disposition. These cash flow estimates require us to make projections and assumptions for many years into the future for pricing, demand, competition, operating cost, contract renewals, and other factors. An asset or asset group is considered impaired when the estimated undiscounted cash flows are less than the carrying amount. In that event, an impairment loss is recognized to the extent that the carrying amount of the asset or asset group exceeds its fair value as determined by quoted market prices in active markets or present value techniques. The determination of fair values using present value techniques requires us to make projections and assumptions regarding future cash flows and weighted average cost of capital. Any changes we make to these projections and assumptions could result in significant revisions to our evaluation of the recoverability of our property, plant and equipment and the recognition of an impairment loss in our consolidated statements of operations.

Goodwill and intangible assets

We record goodwill for the excess of the cost of an acquisition over the fair value of the net assets of the acquired business. Goodwill is not amortized but is reviewed for impairment at least annually or more frequently if an event or change in circumstance indicates that an impairment may have occurred. We first assess qualitative factors to evaluate whether it is more likely than not that an impairment has occurred and it is therefore necessary to perform the two-step goodwill impairment test. If the two-step goodwill impairment test indicates that the goodwill is impaired, an impairment loss is recorded.

We record the estimated fair value of acquired customer contracts, relationships and dedicated acreage agreements as intangible assets. These intangible assets have definite lives and are subject to amortization on a straight-line basis over their economic lives, currently ranging between 10 years and 30 years. We assess intangible assets for impairment together with related underlying long-lived assets whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable.

Deferred financing costs

Costs incurred in connection with our revolving credit facility are deferred and charged to interest expense over the term of the related credit arrangement. Gains or losses on debt repurchase and debt extinguishment include any associated unamortized deferred financing costs.

Asset retirement obligations ("AROs")

AROs are legal obligations associated with the retirement of tangible long-lived assets that result from the asset's acquisition, construction, development and operation. An ARO is initially measured at its estimated fair value. Upon initial recognition, we also record an increase to the carrying amount of the related long-lived asset. We depreciate the asset using the straight-line method over the period during which it is expected to provide benefits. After initial recognition, we revise the ARO to reflect the passage of time and for changes in the estimated amount or timing of cash flows.

We have legal obligations requiring us to decommission our offshore pipeline systems at retirement. In certain rate jurisdictions, we are permitted to include annual charges for removal costs in the regulated cost of service rates we charge our customers. Additionally, legal obligations exist for a minority of our offshore right-of-way agreements due to requirements or landowner options to compel us to remove the pipe at final abandonment. Sufficient data exists with certain onshore pipeline systems to reasonably estimate the cost of abandoning or retiring a pipeline system. However, in some cases, there is insufficient information to reasonably determine the timing and/or method of settlement of estimating the fair value of the asset retirement obligation. In these cases, the asset retirement obligation cost is considered indeterminate because there is no data or information that can be derived from past practice, industry practice, management's experience, or the asset's estimated economic life. The useful lives of most pipeline systems are primarily derived from available supply resources and ultimate consumption of those resources by end users. Variables can affect the remaining lives of the assets which preclude us from making a reasonable estimate of the asset retirement obligation. Indeterminate asset retirement obligation costs will be recognized in the period in which sufficient information exists to reasonably estimate potential settlement dates and methods.

Commitments, contingencies and environmental liabilities

We expense or capitalize, as appropriate, expenditures for ongoing compliance with environmental regulations that relate to past or current operations. We expense amounts we incur from the remediation of existing environmental contamination caused by past operations that do not benefit future periods by preventing or eliminating future contamination. We record liabilities for environmental matters when assessments indicate that remediation efforts are probable and the costs can be reasonably estimated. Estimates of environmental liabilities are based on currently available facts, existing technology and presently enacted laws and regulation taking into consideration the likely effects of inflation and other factors. These amounts also take into account our prior experience in remediating contaminated sites, other companies' clean-up experience and data released by government organizations. Our estimates are subject to revision in future periods based on actual cost or new information. We evaluate recoveries from insurance coverage separately from the liability and, when recovery is probable, we record an asset separately from the associated liability in our consolidated financial statements.

We recognize liabilities for other commitments and contingencies when, after fully analyzing the available information, we determine it is either probable that an asset has been impaired or that a liability has been incurred and the amount of impairment or loss can be reasonably estimated. When a range of probable loss can be estimated, we accrue the most likely amount or if no amount is more likely than another, we accrue the minimum of the range of probable loss. We expense legal costs associated with loss contingencies as such costs are incurred.

Noncontrolling interests

Noncontrolling interests represent the minority interest holders' proportionate share of the equity of the respective systems. Noncontrolling interests are adjusted for the minority interest holders' proportionate share of the earnings or losses. Management reports noncontrolling interest in the Chatom system in the financial statements pursuant to paragraph ASC 810-10-65-1. The 7.8% noncontrolling interest is held by non-affiliated working interest owners.

Revenue recognition and the estimation of revenues and cost of purchases

We recognize revenue when all of the following criteria are met: i) persuasive evidence of an exchange arrangement exists, ii) delivery has occurred or services have been rendered, iii) the price is fixed or determinable, and iv) collectability is reasonably assured. We record revenue and cost of product sold on a gross basis for those transactions where we act as the principal and take title to natural gas, crude oil, NGLs or condensates that are purchased for resale. When our customers pay us a fee for providing a service such as gathering, treating, transportation or storage, we record those fees separately in revenues.

Equity-based compensation

We award equity-based compensation to management, non-management employees and directors under our Long-Term Incentive Plan ("LTIP"), which provides for the issuance of options, unit appreciation rights, restricted units, phantom units, other unit-based awards, unit awards or replacement awards, as well as tandem Distribution Equivalent Rights ("DERs"). Compensation expense is measured by the fair value of the award at the date of grant as determined by management. Compensation expense is recognized in Equity compensation expense over the requisite service period of each award.

Income taxes

The Partnership is not a taxable entity for U.S. federal income tax purposes or for the majority of states that impose an income tax. Taxes on our net income are generally borne by our unitholders through the allocation of taxable income. American Midstream Blackwater, LLC, a subsidiary of the Partnership, owns a subsidiary that has operations which are subject to both federal and state income taxes. We account for income taxes of that subsidiary using an asset and liability approach for financial accounting and reporting of income taxes. If it is more than likely that a deferred tax asset will not be realized, a valuation allowance is recognized.

Certain tax expense results from the enactment of laws by the State of Texas that apply to entities organized as partnerships and is included in Income tax (expense) benefit in our consolidated statements of operations. The Texas margin tax is computed on our taxable margin apportioned to Texas annually.

Net income (loss) for financial statement purposes may differ significantly from taxable income (loss) allocable to unitholders as a result of differences between the financial reporting and income tax bases of our assets and liabilities and the taxable income allocation requirement under our Partnership Agreement. The aggregate difference in the basis of our net assets for financial and tax reporting purposes cannot be readily determined because information regarding each partner's tax attributes in us is not available.

Accumulated other comprehensive income (loss)

Accumulated other comprehensive income (loss) is comprised solely of adjustments related to the Partnership's postretirement benefit plan.

Limited partners' net income (loss) per unit

We compute earnings per unit using the two-class method. The two-class method requires that securities that meet the definition of a participating security be considered for inclusion in the computation of basic earnings per unit. Under the two-class method, earnings per unit is calculated as if all of the earnings for the period were distributed under the terms of the Partnership Agreement, regardless of whether the General Partner has discretion over the amount of distributions to be made in any particular period, whether those earnings would actually be distributed during a particular period from an economic or practical perspective, or whether the General Partner has other legal or contractual limitations on its ability to pay distributions that would prevent it from distributing all of the earnings for a particular period.

The two-class method does not impact our overall net income or other financial results; however, in periods in which aggregate net income exceeds our aggregate distributions for such period, it will have the impact of reducing net income per limited partner unit. This result occurs as a larger portion of our aggregate earnings, as if distributed, is allocated to the incentive distribution rights of the General Partner, even though we make distributions on the basis of available cash and not earnings. In periods in which our aggregate net income does not exceed our aggregate distributions for such period, the two-class method does not have any impact on our calculation of earnings per limited partner unit.

Recent Accounting Pronouncements

In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09, Revenue from Contracts with Customers (Topic 606), which amends the existing accounting standards for revenue recognition. The standard requires an entity to recognize revenue in a manner that depicts the transfer of goods or services to customers at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2015-14 was subsequently issued and deferred the effective date to annual reporting periods beginning after December 15, 2017, including interim reporting periods within that period. We are currently evaluating the method of adoption and impact this standard will have on our consolidated financial statements and related disclosures.

In February 2015, the FASB issued ASU No. 2015-02, Consolidation - Amendments to the Consolidation Analysis, which amends the current consolidation guidance. The amendments affect both the variable interest entity ("VIE") and voting interest entity ("VOE") consolidation models.  The standard is effective for public reporting entities in the fiscal periods beginning after December 15, 2015, early adoption is permitted.  The Partnership has evaluated the impact of this standard on its consolidated financial statements and determined it will not have a material impact.

In April 2015, the FASB issued ASU No. 2015-03, Simplifying the Presentation of Debt Issuance Costs. This amendment requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. ASU 2015-03 is effective for fiscal years beginning after December 15, 2015, including interim periods therein, and is applied retrospectively. Early adoption is permitted for financial statements that have not been previously issued. ASU 2015-15, Presentation and Subsequent Measurement of Debt Issue Costs Associated with Line of Credit Arrangements, was subsequently issued to address the absence of authoritative guidance for debt issuance costs related to line-of-credit arrangements and states that the Securities and Exchange Commission ("SEC") staff will not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement. Given the Partnership's debt issuance costs relate to its Credit Agreement (as defined in Note 13 "Debt Obligations"), the Partnership is not required to alter its current accounting for such costs.

In April 2015, the FASB issued ASU No. 2015-05, Intangibles — Goodwill and Other — Internal-Use Software (Subtopic 350-40), which assists entities in evaluating the accounting for fees paid by a customer in a cloud computing arrangement by providing guidance as to whether an arrangement includes the sales or license of software. The amendment will be effective prospectively for reporting periods beginning on or after December 15, 2015, and early adoption is permitted. The Partnership has evaluated the impact of this standard on its financial statements and determined it will not have a material impact.

In April 2015, the FASB issued ASU No. 2015-06, Earnings Per Share (Topic 260).  This guidance clarifies the process for updating historical earnings per unit disclosures when a drop-down transaction occurs between entities under common control.  Pursuant to the amendment, the earnings (losses) of a transferred business before the date of a dropdown transaction should be allocated entirely to the general partner. Additionally, the previously reported earnings per unit measure presented in the historical financial statements would not change as a result of the drop-down transaction.  ASU 2015-06 is effective for annual reporting periods beginning after December 15, 2015, and for interim periods within those fiscal years.  Early adoption is permitted.  The Partnership has evaluated this guidance and determined it will not have a material impact.

In September 2015, the FASB issued ASU No. 2015-16, Business Combinations (Topic 805). This amendment requires that an acquirer recognize adjustments to provisional amounts that are identified during the measurement period in the reporting period in which the adjustment amounts are determined. ASU 2015-16 is effective for fiscal years beginning after December 15, 2015, including interim periods within those fiscal years. Early adoption is permitted for financial statements that have not been issued. The Partnership has evaluated this guidance and determined it is consistent with our policy and historical presentation.

In November 2015, the FASB issued ASU 2015-17, Income Taxes (Topic 740). This amendment requires that deferred tax liabilities and assets be classified as noncurrent. ASU 2015-17 is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early adoption is permitted. The Partnership has evaluated this guidance and elected to adopt this amendment for the fiscal year ended December 31, 2015. As such, the Partnership’s deferred tax liabilities and assets have been classified as noncurrent in the consolidated balance sheets as of December 31, 2015, and 2014.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). This amendment requires the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous GAAP. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. We are currently evaluating the method of adoption and impact this standard will have on our consolidated financial statements and related disclosures.
Acquisitions
Acquisitions
Acquisitions and Divestitures

Delta House Investment

On September 18, 2015, the Partnership acquired a 26.3% interest in Pinto Offshore Holdings, LLC ("Pinto") (the "Delta House Investment"), an entity that owns a non-operated interest in (i) approximately 49% of the limited liability company interests of Delta House FPS LLC and (ii) approximately 49% of the limited liability company interests of Delta House Oil and Gas Lateral LLC, which respectively own Delta House floating production system and related pipeline infrastructure.  Delta House is a floating production system platform with associated crude oil and gas export pipelines, located in the Mississippi Canyon region of the deepwater Gulf of Mexico.

We acquired our 26.3% non-operated interest in Pinto in exchange for $162.0 million in cash, funded by the proceeds of a public offering of 7.5 million of the Partnership's common units representing Limited Partner interests, or common units, and with borrowings under the Partnership's Credit Agreement. As a result, we own a minority interest in Pinto, which represents an indirect 12.9% interest in Delta House. Pursuant to the Pinto LLC Agreement, we have no management control or authority over the day-to-day operations.  Our interest in Pinto is accounted for as an equity method investment in the consolidated financial statements.

Because our interest in Delta House was previously owned by an affiliate of our General Partner, we have accounted for our investment at our affiliate's final carry-over basis resulting in $65.7 million which is recorded in Investments in unconsolidated affiliates in our consolidated balance sheets and as an investing activity within the related consolidated statement of cash flows. The amount by which the total consideration exceeded the carry-over basis was $96.3 million and is recorded as a distribution within the consolidated statements of changes in partners’ capital and noncontrolling interest and a financing activity in the consolidated statement of cash flows.

For the year ended December 31, 2015, the Partnership recorded $7.5 million in earnings from its indirect interest in Delta House and also received cash distributions of $16.6 million from Delta House. The excess of the cash distributions received over the earnings recorded is classified as a return of capital within cash flows from investing activities in our consolidated statement of cash flows.

Costar Acquisition

On October 14, 2014, the Partnership acquired 100% of the membership interests of Costar Midstream, L.L.C. ("Costar") from Energy Spectrum Partners VI LP and Costar Midstream Energy, LLC, in exchange for $258.0 million in cash and 6.9 million of the Partnership's common units ("the Costar Acquisition"). Costar is an onshore gathering and processing company with its primary gathering, processing, fractionation, and off-spec condensate treating and stabilization assets in East Texas and the Permian basin, with a significant crude oil gathering system project in the Bakken oil play.

The Costar Acquisition was accounted for using the acquisition method of accounting and as a result, the aggregate purchase price was allocated to the assets acquired, liabilities assumed and a noncontrolling interest in a Costar subsidiary based on their respective fair values as of the acquisition date. The excess of the aggregate purchase price of the fair values of the assets acquired, liabilities assumed and the noncontrolling interest was classified as goodwill, which is attributable to future prospective customer agreements expected to be obtained as a result of the acquisition. The operating systems acquired have been included in the Partnership’s Gathering and Processing segment from the acquisition date.

The following table summarizes the fair value of consideration transferred to acquire Costar and the allocation of that amount to the assets acquired, liabilities assumed and the noncontrolling interest for the Costar Acquisition based upon their respective fair values as of the acquisition date (in thousands).
Fair value of consideration transferred (in thousands):
 
Cash
$
258,001

Limited partner common units
147,296

Total fair value of consideration
$
405,297


Fair Value of assets acquired, liabilities assumed and noncontrolling interest (in thousands):
 
Working capital
$
8,152

Property, plant and equipment:
 
Processing plants
$
48,357

Pipelines
128,799

Land
1,244

Buildings
682

Equipment
9,827

Construction in progress
16,146

Total property, plant and equipment
205,055

Investment in unconsolidated affiliate
11,884

Intangible assets:
 
Customer relationships
53,400

Dedicated acreage
32,000

Goodwill
95,025

Noncontrolling interest
(219
)
 
$
405,297



The fair value of the common units issued for the Costar Acquisition, $147.3 million, differs from the market price of such units on the date of the acquisition as a result of restrictions which require the sellers to hold the units for specified periods of time. The fair value of limited partner units issued in the transaction was determined using an option pricing model and the following key assumptions: i) the closing common unit market price on the day of the acquisition, ii) the contractual holding periods, iii) historical common unit price volatility for the Partnership and its peers, and iv) a risk-free rate of return.

The fair value of property, plant and equipment was determined using both the cost and market approaches which required significant Level 3 inputs. Key assumptions included i) estimated replacement costs for individual assets or asset groups, ii) estimated remaining useful lives for the acquired assets, and iii) recent market transactions for similar assets. The fair value of intangible assets was determined using the income approach which also required significant Level 3 inputs. Key assumptions included i) estimated throughput volumes, ii) forward market prices for natural gas and NGLS as of the acquisition date, iii) estimated future operating and development cash flows, and iv) discount rates ranging from 11.0% to 16.0%.

The intangible assets acquired relate to existing customer relationships which Costar had at the time of the acquisition, as well as agreements with two producers under which Costar agreed to construct and operate gathering and processing facilities in exchange for the producers’ agreements to dedicate certain acreage and related production to those facilities. Working capital includes $11.2 million of accounts receivable, all of which were subsequently collected.

During 2015, the Partnership reached agreements with the Costar sellers regarding certain matters which resulted in a return of $7.4 million of cash to the Partnership and related reductions in the goodwill initially recorded. Additionally, in February 2016, the Partnership reached a settlement of certain indemnification claims with the Costar sellers whereby 1,034,483 common units held in escrow were returned to the Partnership, while the Partnership agreed to pay the Costar sellers an additional $0.3 million. The net impact of this settlement will be recorded as a reduction in property, plant and equipment in the first quarter of 2016. As described in Note 9 "Goodwill and Intangible Assets, net", the Partnership recognized a $95.0 million impairment of the remaining Costar goodwill during the fourth quarter of 2015.

Costar contributed revenue of $19.9 million and operating income of $0.3 million for the period of October 14, 2014 through December 31, 2014, which was attributable to the Partnership's Gathering and Processing segment. Additionally, the Partnership incurred $0.5 million of transaction costs related to the acquisition which are included in Selling, general and administrative expenses in our consolidated statement of operations for the year ended December 31, 2014. The following unaudited pro forma summary presents consolidated financial information for the Partnership as if the Costar acquisition had occurred on January 1, 2013 (in thousands):
 
Years Ended December 31,
 
2014
 
2013
Revenue
$
435,133

 
$
448,748

Net loss
(101,237
)
 
(30,672
)
Limited partners' net loss per unit
(6.15
)
 
(3.82
)


These pro forma amounts have been calculated after applying the Partnership’s accounting policies to Costar’s historical results and making adjustments to reflect additional interest expense that would have been incurred and additional depreciation and amortization expense that would have been recognized had the acquisition occurred as of January 1, 2013. The unaudited pro forma adjustments are based on available information and certain assumptions we believe are reasonable.

Lavaca Acquisition

On January 31, 2014, the Partnership acquired approximately 120 miles of high- and low-pressure pipelines and associated facilities located in the Eagle Ford shale in Gonzales and Lavaca Counties, Texas from Penn Virginia Corporation (NYSE: PVA) ("PVA") for $104.4 million in cash (the "Lavaca Acquisition"). The Lavaca Acquisition was financed with proceeds from the Partnership's January 2014 equity offering and from the issuance of Series B Units to our General Partner.

The Lavaca Acquisition was accounted for using the acquisitions method of accounting and, as a result, the purchase price was allocated to the assets acquired upon their respective fair values as of the acquisition date. The excess of the purchase price over the fair value of the assets acquired was classified as goodwill.

The following table summarizes the final allocation of the purchase price to the assets acquired in the Lavaca Acquisition based upon their respective fair values as of the acquisition date (in thousands):
Property, plant and equipment:
 
Land
$
2

Pipelines
58,737

Equipment
753

Total property, plant and equipment
59,492

Intangible assets
21,350

Goodwill
23,567

Total cash consideration
$
104,409



The fair value of property, plant and equipment was determined using the cost approach which required significant Level 3 inputs. Key assumptions included i) estimated replacement costs for individual assets or asset groups and ii) estimated remaining useful lives for the acquired assets. The fair value of intangible assets was determined using the income approach which also required significant Level 3 inputs. Key assumptions included i) estimated throughput volumes, ii) future operating and development cash flows, and iii) a discount rate of 10.5%.

The intangible assets acquired relate to a 25-year gas gathering agreement under which PVA will dedicate certain acreage and related production to the acquired facilities.

As described in Note 9 "Goodwill and Intangible Assets, net", the Partnership recognized a $23.6 million impairment of the remaining Lavaca goodwill during the fourth quarter of 2015.

Lavaca contributed revenue of $16.8 million and net income of $7.6 million for the period from January 31, 2014 through December 31, 2014, attributable to the Partnership's Gathering and Processing segment. The Partnership incurred $0.1 million of transaction costs related to the acquisition, which are included in Selling, general and administrative expenses in our consolidated statement of operations for the year ended December 31, 2014.

Pro forma financial information to show the impact on the Partnership’s financial information as if the Lavaca acquisition had been completed on January 1, 2013, have not been presented as the Partnership was unable to obtain the necessary information from the seller.

Other Acquisitions

Investment in Unconsolidated Affiliate

On August 11, 2014, the Partnership acquired a 66.7% non-operated interest in MPOG, an offshore crude oil gathering system, for a net purchase price of $12.0 million, which was financed with borrowings from the Partnership's credit facility. Although the Partnership owns a majority interest in MPOG, the ownership structure requires unanimous approval of all owners on decisions impacting the operation of the assets and any changes in ownership structure. Therefore, the Partnership's voting rights are not proportional to its obligation to absorb losses or receive returns. The Partnership accounts for its 66.7% interest using the equity method.

For the year ended December 31, 2015, the Partnership recorded $0.7 million in earnings from MPOG, and received cash distributions of $3.9 million. For the year ended December 31, 2014, the Partnership recorded $0.3 million in earnings from MPOG, and received cash distributions of $2.0 million. The excess of the cash distributions received over the earnings recorded from MPOG is classified as a return of capital within cash flows from investing activities in our consolidated statements of cash flows.

Williams Pipeline Acquisition

In the first quarter of 2014, the Partnership acquired natural gas pipeline facilities that are contiguous to and connect with our High Point System in offshore Louisiana from Transcontinental Gas Pipe Line Company, LLC ("Transco"), a subsidiary of Williams Partners, LP for $6.5 million  in cash (the "Williams Pipeline Acquisition"). The acquisition was subject to FERC approval of the seller's application to abandon the pipeline facilities to us by sale and to permit the facilities to serve a gathering function, exempt from FERC's jurisdiction. The FERC granted approval of the application during the first quarter of 2014, and the purchase and sale agreement closed on March 14, 2014. The purchase price was allocated to pipelines using the income approach which required certain Level 3 inputs.

Blackwater Terminals Acquisition

On December 17, 2013, the Partnership acquired Blackwater Midstream Holdings LLC ("Blackwater"), a Delaware limited liability company and other related subsidiaries from an affiliate of HPIP. Blackwater operated 1.3 million barrels of storage capacity across four marine terminal sites located in Westwego, Louisiana; Brunswick, Georgia; Harvey, Louisiana; and Salisbury, Maryland.

Because Blackwater was previously owned by an affiliate our General Partner, we have accounted for the acquisition at our General Partner's carry-over basis. The Partnership' total consideration distributed for the acquisition was $63.9 million. The amount by which the total consideration exceeded the carry-over basis was $27.7 million and was recorded as a distribution within the consolidated statements of changes in partners’ capital and noncontrolling interest and as a financing activity in the consolidated statement of cash flows. The consideration also included 125,500 limited partner units which were accounted for as a non-cash distribution to the General Partner at a fair value of $3.1 million. The fair value of the units issued was determined using level one inputs based upon the Partnership's closing unit price on December 17, 2013.

The remaining consideration was utilized to settle all of the Blackwater's outstanding debt at December 17, 2013.

The acquisition of Blackwater represents a transaction between entities under common control and a change in reporting entity. Transfers of net assets or exchanges of shares between entities under common control are accounted for as if the transfer occurred at the beginning of the period or date of common control. Therefore, net assets received were recorded at their historical book value of $22.7 million as of the date common control was established, which is April 15, 2013.

For the period from April 15, 2013 to December 31, 2013, our Blackwater contributed $9.8 million of revenue and $0.8 million of net loss attributable to the Partnership's Terminals segment, which are included in the consolidated statements of operations.

High Point System

Effective April 15, 2013, an affiliate of our General Partner contributed the High Point System, consisting of 100% of the limited liability company interests in High Point Gas Transmission, LLC, and High Point Gas Gathering, LLC. The High Point System consists of approximately 700 miles of natural gas and liquids pipeline assets located in southeast Louisiana, in the Plaquemines and St. Bernard parishes, and the shallow water and deep shelf Gulf of Mexico, including the Mississippi Canyon, Viosca Knoll, West Delta, Main Pass, South Pass and Breton Sound zones. Natural gas is collected at more than 75 receipt points that connect hundreds of wells with an emphasis on oil and liquids-rich reservoirs.

The High Point System, along with $15.0 million in cash, was contributed to us by HPIP in exchange for 5,142,857 Series A Units. Of the cash consideration paid by HPIP, approximately $2.5 million was used to pay certain transaction expenses of HPIP, and the remaining approximately $12.5 million was used to repay borrowings outstanding under the Partnership's former credit facility. The contribution of the High Point System occurred concurrently with HPIP's acquisition of 90% of our General Partner and all of our subordinated units, which resulted in HPIP gaining control of our General Partner and a majority of our outstanding limited partner interests.

The fair value of the Series A Units on April 15, 2013, was $17.50 per unit, or a total of $90.0 million, and was issued by the Partnership in exchange for net cash of approximately $12.5 million and net assets of $61.9 million contributed to the Partnership by our General Partner. Because the High Point System was previously owned by our General Partner, we have accounted for this acquisition at our General Partner's final carry-over basis. As such, the amount by which the value of the Series A Units exceeded the carry-over basis of the net assets contributed by our General Partner was $15.6 million and was recorded as a distribution to our General Partner and existing limited partners' interest based on their ownership interests within the consolidated statements of changes in partners’ capital and noncontrolling interest.

The fair value measurement was based on significant inputs not observable in the market and thus represents a Level 3 measurement as defined by ASC 820. Primarily using the income approach, the fair value estimate was based on i) present value of estimated future contracted distributions, ii) an assumed discount rate of 18.0%, and iii) an assumed distribution growth rate of 1.0% in 2014 and thereafter.

Subsequent to the contribution, for the year ended December 31, 2013, the High Point System contributed $30.4 million of revenue and $7.2 million of net income attributable to the Partnership's Transmission segment, which are included in the consolidated statements of operations.

Divestitures

On September 14, 2015, the Partnership disposed of certain terminal assets in Salisbury, Maryland, that were previously held for sale, with a book value approximating the sales proceeds of $0.9 million, resulting in a non-cash loss on disposal of less than $0.1 million. Of the proceeds received, the Partnership distributed $0.5 million to our General Partner in accordance with the Agreement and Plan of Merger.

On June 1, 2015, the Partnership disposed of certain non-strategic off-shore transmission assets in Louisiana with a net book value of $3.0 million for nominal proceeds, resulting in a non-cash loss on disposal of $3.0 million.

On March 31, 2014, the Partnership completed the sale of certain gathering and processing assets in Madison County, Texas, in exchange for $6.1 million in cash which resulted in a nominal gain. The Partnership recognized a $3.0 million impairment charge related to these assets for the year ended December 31, 2013, to reduce the related carrying value of $6.1 million.
Discontinued Operations (Notes)
Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]
Discontinued Operations

During 2013, the Board of Directors of our General Partner approved a plan to sell certain non-strategic gathering and processing assets which met specific criteria, qualifying them as held for sale. During the year ended December 31, 2013, certain gathering and processing assets were written down by $1.8 million to the estimated fair value less cost to sell. These fair value measurements were based on significant inputs not observable in the market and thus represent a Level 3 measurement as defined by ASC 820. Primarily using the income approach, the fair value estimates were based on i) present value of estimated EBITDA, ii) an assumed discount rate of 10%, and iii) a decline in throughput volumes of 2.5% in 2013 and thereafter.

During the second quarter of 2014, the Partnership’s management decided not to sell a portion of the assets that had previously been reclassified to discontinued operations and assets held for sale in the second quarter of 2013. In accordance with ASC 360, the Partnership reclassified the assets as held and used at the carrying value of the assets before they were classified as held for sale, adjusted for depreciation expense that would have been recorded. The Partnership has reclassified the amounts recorded in discontinued operations related to the assets for all prior periods presented.

As part of the Blackwater Acquisition, we acquired long-lived terminal assets which were immediately classified as held for sale. As of December 31, 2013, these assets were written down by $0.6 million to the estimated fair value less cost to sell. As a result of deteriorating market conditions, the Partnership recognized an additional impairment charge on these assets of $0.7 million in 2014. These assets were sold during the third quarter of 2015 at a nominal loss.

Historically, we have classified these assets as discontinued operations within our consolidated statements of operations. We elected not to separately present the operating, investing and financing cash flows related to the disposal groups in our accompanying consolidated statements of cash flows as this activity was immaterial for all periods presented.

The following table presents the revenue, expense and (loss) gain from discontinued operations associated with the assets classified as held for sale for the years ended December 31, 2015, 2014, and 2013 (in thousands, except per unit amounts):

 
Years Ended December 31,
 
2015
 
2014
 
2013
Revenue
$
74

 
$
474

 
$
2,084

Expense
(196
)
 
(658
)
 
(2,361
)
Impairment
—

 
(673
)
 
(2,400
)
Loss on sale of assets
(150
)
 
(87
)
 
(75
)
Income tax benefit
192

 
333

 
339

Income (loss) from discontinued operations, net of tax
$
(80
)
 
$
(611
)
 
$
(2,413
)
Limited partners' net income (loss) per unit from discontinued operations (basic and diluted)
$
—

 
$
(0.04
)
 
$
(0.27
)
Concentration of Credit Risk and Trade Accounts Receivable
Concentration Risk Disclosure [Text Block]
Concentration of Credit Risk and Trade Accounts Receivable

Our primary assets, which are strategically located in Alabama, Georgia, Louisiana, Mississippi, North Dakota, Tennessee, Texas and the Gulf of Mexico, provide critical infrastructure that links customers of natural gas, crude oil, NGLs, condensate and specialty chemicals to numerous intermediate and end-use markets.  As a result of recent acquisitions and geographic diversification, we have reduced the concentration of trade receivable balances due from these customer groups, and reduced the concentration which may affect our overall credit risk. Our customers' historical financial and operating information is analyzed prior to extending credit. We manage our exposure to credit risk through credit analysis, credit approvals, credit limits and monitoring procedures, and for certain transactions, we may request letters of credit, prepayments or guarantees. We record allowances for potentially uncollectible accounts receivable when necessary; however, for the years ended December 31, 2015, 2014 and 2013, no allowances or significant write-offs of accounts receivable were required.

The following table summarizes those customers who accounted for more than 10% of the Partnership's consolidated revenue for the each of the last three years:

 
Years Ended December 31,
 
2015
 
2014
 
2013
Customer A
10
%
 
22
%
 
28
%
Customer B
—
%
 
—
%
 
13
%
Customer C
—
%
 
12
%
 
12
%
Customer D
—
%
 
10
%
 
10
%
Other
90
%
 
56
%
 
37
%
Total
100
%
 
100
%
 
100
%
Other Current Assets
Other Current Assets
Other Current Assets

Other current assets consists of the following (in thousands):
 
December 31,
 
2015
 
2014
Prepaid insurance—current portion
$
3,948

 
$
4,162

Restricted cash
—

 
6,475

Other prepaid amounts
2,866

 
758

Other current assets
3,280

 
4,159

 
$
10,094

 
$
15,554



Restricted cash of $6.5 million as of December 31, 2014 consisted of a cash-backed letter of credit related to Costar operations that the Partnership was contractually obligated to maintain after the Costar Acquisition. The Partnership was released from this obligation in January 2015. Other current assets primarily consist of natural gas imbalances and amounts due from related parties.
Derivatives
Derivatives
Derivatives

Commodity Derivatives

To minimize the effect of commodity price changes and maintain our cash flow and the economics of our development plans, we enter into commodity hedge contracts from time to time. The terms of the contracts depend on various factors, including management's view of future commodity prices, economics on purchased assets and future financial commitments. This hedging program is designed to mitigate the effect of commodity price declines while allowing us to participate in some commodity price upside. Management regularly monitors the commodity markets and financial commitments to determine if, when, and at what level commodity hedging is appropriate in accordance with policies that are established by the Board of Directors of our General Partner. Due to declining prices, we had not entered into commodity hedge contracts to hedge production in 2016 and beyond as of December 31, 2015.

From time to time, we enter into commodity contracts with multiple counterparties, and in some cases, may be required to post collateral with our counterparties in connection with our derivative positions. As of December 31, 2015, we had not posted collateral with our counterparties. The counterparties are not required to post collateral with us in connection with their derivative positions. Netting agreements are in place that permit us to offset our commodity derivative asset and liability positions with our counterparties. We did not designate any of our commodity derivatives as hedges for accounting purposes. As a result, our commodity derivatives are accounted for at fair value in our consolidated balance sheets with changes in fair value recognized currently in earnings.

Interest Rate Swap

To manage the impact of the interest rate risk associated with our Credit Agreement we enter into interest rate swaps from time to time, effectively converting a portion of the cash flows related to our long-term variable rate debt into fixed rate cash flows. The notional amount of our interest rate swap that expired on August 1, 2015 was $100.0 million. The interest rate swap was entered into with a single counterparty and we were not required to post collateral. On March 2, 2016, we entered into interest rate swaps with a notional amount of $200.0 million that will expire in September 2019.

Weather Derivative

In the second quarters of 2015 and 2014, we entered into weather derivatives to mitigate the impact of potential unfavorable weather to our operations under which we could receive payments totaling up to $10.0 million in the event that a hurricane or hurricanes of certain strength pass through the area as identified in the derivative agreement. The weather derivatives are accounted for using the intrinsic value method, under which the fair value of the contract was zero and any amounts received are recognized as gains during the period received. The weather derivatives were entered into with a single counterparty and we were not required to post collateral.

We paid premiums of $0.9 million and $1.0 million in 2015 and 2014, respectively, which are recorded as current Risk management assets on the consolidated balance sheets and are amortized to Direct operating expenses on a straight-line basis over the term of the contract of 1 year. Unamortized amounts associated with weather derivatives were approximately $0.4 million and $0.4 million as of December 31, 2015 and 2014, respectively.

As of December 31, 2015 and 2014, the value associated with our commodity derivatives, interest rate swap and weather derivative were recorded in our consolidated balance sheets, under the captions as follows (in thousands):
 
 
Gross Risk Management Assets
 
Gross Risk Management Liabilities
 
Net Risk Management Assets (Liabilities)
Balance Sheet Classification
 
December 31, 2015
 
December 31, 2014
 
December 31, 2015
 
December 31, 2014
 
December 31, 2015
 
December 31, 2014
Current
 
$
365

 
$
688

 
$
—

 
$
—

 
$
365

 
$
688

Noncurrent
 
—

 
—

 
—

 
—

 
—

 
—

Total assets
 
$
365

 
$
688

 
$
—

 
$
—

 
$
365

 
$
688

 
 
 
 
 
 
 
 
 
 
 
 
 
Current
 
$
—

 
$
—

 
$
—

 
$
(215
)
 
$
—

 
$
(215
)
Noncurrent
 
—

 
—

 
—

 
—

 
—

 
—

Total liabilities
 
$
—

 
$
—

 
$
—

 
$
(215
)
 
$
—

 
$
(215
)

For the years ended December 31, 2015, 2014 and 2013, the realized and unrealized gains (losses) associated with our commodity, interest rate and weather derivative instruments were recorded in our consolidated statements of operations, under the captions as follows (in thousands):
 
 
Realized
 
Unrealized
2015
 

Gain (loss) on commodity derivatives, net
 
$
1,610

 
$
(286
)
Interest expense
 
(240
)
 
215

Direct operating expenses
 
(913
)
 
—

Total
 
$
457

 
$
(71
)
2014
 
 
 
 
Gain (loss) on commodity derivatives, net
 
$
735

 
$
356

Interest expense
 
(433
)
 
239

Direct operating expenses
 
(1,035
)
 
—

Total
 
$
(733
)
 
$
595

2013
 
 
 
 
Gain (loss) on commodity derivatives, net
 
$
1,069

 
$
(1,041
)
Interest expense
 
(207
)
 
(454
)
Direct operating expenses
 
(662
)
 
—

Total
 
$
200

 
$
(1,495
)
Fair Value Measurement
Fair Value Measurement
Fair Value Measurement

We believe the carrying amount of cash and cash equivalents, accounts receivable and accounts payable approximate fair value because of the short-term maturity of these instruments.

The recorded value of the amounts outstanding under the Credit Agreement approximates its fair value, as interest rates are variable, based on prevailing market rates and the short-term nature of borrowings and repayments under the Credit Agreement.

The fair value of all derivatives instruments is estimated using a market valuation methodology based upon forward commodity price curves, volatility curves as well as other relevant economic measures, if necessary. Discount factors may be utilized to extrapolate a forecast of future cash flows associated with long dated transactions or illiquid market points. The inputs are obtained from independent pricing services, and we have made no adjustments to the obtained prices.

We have consistently applied these valuation techniques in all periods presented and believe we have obtained the most accurate information available for the types of derivatives contracts held. We will recognize transfers between levels at the end of the reporting period for which the transfer has occurred. There were no such transfers during 2015, 2014 or 2013.

Fair Value of Financial Instruments

The following table sets forth by level within the fair value hierarchy, our commodity derivative instruments and interest rate swap, included as part of Risk management assets and Risk management liabilities within the consolidated balance sheets, that were measured at fair value on a recurring basis as of December 31, 2015 and 2014 (in thousands):

 
Carrying
Amount
 
Estimated Fair Value of the Asset (Liability)
 
Level 1
 
Level 2
 
Level 3
 
Total
Commodity derivative instruments, net
 
 
 
 
 
 
 
 
 
December 31, 2015
$
—

 
$
—

 
$
—

 
$
—

 
$
—

December 31, 2014
286

 
—

 
286

 
—

 
286

Interest rate swap
 
 
 
 
 
 
 
 
 
December 31, 2015
$
—

 
$
—

 
$
—

 
$
—

 
$
—

December 31, 2014
(215
)
 
—

 
(215
)
 
—

 
(215
)

The unamortized portion of the premium paid to enter the weather derivative described in Note 6 "Derivatives," is included within Risk management assets on the consolidated balance sheets but is not included in the above table as it is recorded at amortized cost, not fair value.
Property, Plant and Equipment, Net
Property, Plant and Equipment, Net
Property, Plant and Equipment, Net

Property, plant and equipment, net, as of December 31, 2015 and 2014, were as follows (in thousands):
 
 
Useful Life
(in years)
 
December 31,
2015
 
December 31,
2014
Land
N/A
 
$
5,282

 
$
5,282

Construction in progress
N/A
 
46,045

 
77,550

Buildings and improvements
4 to 40
 
9,864

 
6,855

Processing and treating plants
8 to 40
 
97,784

 
80,837

Pipelines and compressors
3 to 40
 
554,400

 
476,997

Storage
20 to 40
 
58,394

 
38,151

Equipment
5 to 20
 
22,207

 
12,345

Total property, plant and equipment
 
 
793,976

 
698,017

Accumulated depreciation
 
 
(145,963
)
 
(115,835
)
Property, plant and equipment, net
 
 
$
648,013

 
$
582,182



Of the gross property, plant and equipment balances at December 31, 2015 and 2014, $111.9 million and $101.9 million, respectively, related to our FERC regulated interstate and intrastate assets.

Capitalized interest was $1.9 million, $0.8 million and $0.2 million for the years ended December 31, 2015, 2014 and 2013, respectively.

Depreciation expense was $31.9 million, $23.9 million and $25.9 million for the years ended December 31, 2015, 2014 and 2013, respectively.

2014 Impairments

During the fourth quarter of 2014, management noted the declining commodity markets and related impact on producers and shippers to whom we provide gathering and processing services. The decline in the market price of crude oil led to a corresponding decrease in natural gas and crude oil production impacting the volume of natural gas and NGLs we gather and process on certain assets. As a result, an asset impairment charge of $99.9 million was recorded in the three months ended December 31, 2014. These fair value measurements are based on significant inputs not observable in the market and thus represented a Level 3 measurement as defined by ASC 820. Primarily using the income approach, the fair value estimates were based on i) present value of estimated EBITDA, ii) an assumed discount rate of 9.5%, and iii) the expected remaining useful life of the asset or asset group. See Note 3 "Discontinued Operations" for discussion related to additional impairments.

2013 Impairments

During 2013, management changed its commercial approach towards certain non-strategic gathering and processing assets. As a result, an asset impairment charge of $15.2 million was recorded in the three months ended June 30, 2013. These fair value measurements were based on significant inputs not observable in the market and thus represented a Level 3 measurement as defined by ASC 820. Primarily using the income approach, the fair value estimates were based on i) present value of estimated EBITDA, ii) an assumed discount rate of 10%, and iii) a decline in throughput volumes of 2.5% in 2013 and thereafter.
Goodwill and Intangible assets (Notes)
Goodwill and Intangible Assets Disclosure [Text Block]
Goodwill and Intangible Assets, Net

Management performs an annual goodwill assessment at the reporting unit level. This annual goodwill assessment is based on fair value measurements that are based on significant inputs not observable in the market and thus represent a Level 3 measurement as defined by ASC 820. In its assessment, management primarily uses a discounted cash flow analysis, supplemented by a market approach analysis. Key assumptions in the analysis include the use of an appropriate discount rate, volume forecasts, storage utilization, terminal year multiples, and estimated future cash flows including an estimate of operating costs, and maintenance capital expenditures. In estimating cash flows, management incorporates current market information, as well as historical and other factors into the forecasted commodity prices and contracted rates used.

Management utilized the fair value approach described above in performing step one of its annual goodwill impairment test during the fourth quarter of 2015. As a result of our step one analysis, we determined that the estimated fair value of certain reporting units within our Gathering and Processing reportable segment were less than their respective carrying amounts, primarily due to changes in assumptions related to commodity prices, timing of estimated drilling by producers, and discount rates. The changes in the assumptions noted were adversely impacted by the continuing decline in market conditions within the energy sector.

The second step of the goodwill impairment test involves allocating the estimated fair value of each reporting unit among the assets and liabilities of the reporting unit in a hypothetical purchase price allocation. The results of the hypothetical purchase price allocation indicated there was no fair value attributable to goodwill of the reporting units within our Gathering and Processing reportable segment. As a result, we recognized a Loss on impairment of goodwill of $118.6 million during the fourth quarter of 2015. The impairment consisted of $95.0 million and $23.6 million related to the Costar and Lavaca Acquisitions, respectively.

The carrying value of goodwill as of December 31, 2015 and 2014, was $16.3 million and $142.2 million, respectively. Goodwill as of December 31, 2015 related to our Terminal segment, while $125.9 million and $16.3 million related to our Gathering and Processing and Terminal segment, respectively, as of December 31, 2014.

The goodwill associated with our Terminal segment was obtained primarily as part of the Blackwater Acquisition described in Note 2 "Acquisitions and Divestitures".

Intangible assets, net, consists of customer contracts, relationships and dedicated acreage agreements identified as part of the Costar, Lavaca and Blackwater acquisitions. These intangible assets have definite lives and are subject to amortization on a straight-line basis over their economic lives, currently ranging from 10 years to 30 years. Intangible assets, net, consist of the following (in thousands):
 
December 31,
 
2015
 
2014
Gross carrying amount:
 
 
 
    Customer contracts
$
12,101

 
$
12,101

    Customer relationships
53,400

 
53,400

    Dedicated acreage
53,350

 
53,350

 
$
118,851

 
$
118,851

Accumulated amortization:
 
 
 
    Customer contracts
$
(12,101
)
 
$
(11,110
)
    Customer relationships
(3,124
)
 
(553
)
    Dedicated acreage
(2,661
)
 
(882
)
 
$
(17,886
)
 
$
(12,545
)
Net carrying amount:
 
 
 
    Customer contracts
$
—

 
$
991

    Customer relationships
50,276

 
52,847

    Dedicated acreage
50,689

 
52,468

 
$
100,965

 
$
106,306



For the years ended December 31, 2015, 2014 and 2013, amortization expense on our intangible assets totaled $5.3 million, $4.1 million and $3.7 million, respectively. Estimated amortization expense for each of the next five fiscal years (2016 – 2020) is approximately $4.3 million per year.
Investment in unconsolidated affiliates (Notes)
Equity Method Investments and Joint Ventures Disclosure [Text Block]
10. Investment in Unconsolidated Affiliates

The following table presents the activity in the Partnership's equity investments (in thousands):

 
 
MPOG
 
Mesquite
 
Pinto/Delta House
 
Total
 
 
66.7%
 
46%
 
12.9%
 
 
Balances at December 31, 2013
$
—

 
$
—

 
$
—

 
$
—

 
Initial investment
12,000

 
11,884

 
—

 
23,884

 
Earnings in unconsolidated affiliates
348

 
—

 
—

 
348

 
Distributions
(1,980
)
 
—

 
—

 
(1,980
)
Balances at December 31, 2014
$
10,368

 
$
11,884

 
$
—

 
$
22,252

 
Initial investment
—

 
—

 
65,703

 
65,703

 
Earnings in unconsolidated affiliates
731

 
—

 
7,470

 
8,201

 
Contributions
—

 
6,713

 
—

 
6,713

 
Distributions
(3,920
)
 
—

 
(16,648
)
 
(20,568
)
Balances at December 31, 2015
$
7,179

 
$
18,597

 
$
56,525

 
$
82,301



The following tables present the summarized combined financial information for the Partnership's equity investments (amounts represent 100% of investee financial information):

 
Years Ended December 31,
Balance Sheets:
2015
 
2014
Current assets
$
2,086

 
$
2,196

Non-current assets
288,617

 
62,635

Current liabilities
366

 
398

Non-current liabilities
23,617

 
22,307


 
Years Ended December 31,
Income Statements:
2015
 
2014
 
2013
Total revenue
$
37,724

 
$
3,847

 
$
—

Operating expense
3,375

 
1,722

 
—

Net income
29,437

 
510

 
—



The unconsolidated affiliates described above were each determined to be Variable Interest Entities ("VIE") due to disproportionate economic interests and decision making rights. In each case, the Partnership lacks the power to direct the activities that most significantly impact each unconsolidated affiliate's economic performance. As the Partnership does not hold a controlling financial interest in these affiliates, the Partnership accounts for its related investments using the equity method. The Partnership’s maximum exposure to loss related to each VIE is limited to its equity investment as presented on the consolidated balance sheet at December 31, 2015. In each case, the Partnership is not obligated to absorb losses greater than its proportional ownership percentages indicated above. In each case, the Partnership’s right to receive residual returns is not limited to any amount less than the proportional ownership percentages indicated above.
Accrued Expenses and Other Current Liabilities
Accounts Expenses and Other Current Liabilities
Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities were as follows (in thousands):

 
 
December 31,
 
 
2015
 
2014
Current portion of asset retirement obligation
 
$
6,822

 
$
—

Accrued capital expenditures
 
3,984

 
17,134

Accrued expenses
 
3,178

 
4,560

Due to related parties
 
3,894

 
659

Gas imbalances payable
 
413

 
1,055

Other
 
6,744

 
2,392

 
 
$
25,035

 
$
25,800

Asset Retirement Obligation
Asset Retirement Obligation
Asset Retirement Obligations

The following table presents activity in the Partnership's asset retirement obligations (in thousands):
 
Years Ended December 31,
 
2015
 
2014
Beginning asset retirement obligation
$
34,645

 
$
34,636

Liabilities assumed
—

 
248

Expenditures
(91
)
 
(1,030
)
Accretion expense
817

 
791

Total ending asset retirement obligation
35,371

 
34,645

Less: current portion
6,822

 
—

Long-term asset retirement obligation
$
28,549

 
$
34,645



We are required to establish security against any potential secondary obligations relating to the abandonment of certain transmission assets that may be imposed on the previous owner by applicable regulatory authorities. As such, we have a restricted cash account maintained by a third party that amounted to $5.0 million as of December 31, 2015 and 2014, respectively, and is presented in Other assets, net in our consolidated balance sheets.
Debt Obligations
Debt Obligations

Our outstanding borrowings under the credit facility were (in thousands):
 
 
December 31,
 
 
2015
 
2014
Revolving credit facility
 
$
525,100

 
$
372,950

Other debt
 
2,338

 
2,908

Total debt
 
527,438

 
375,858

Less: current portion
 
2,338

 
2,908

Long-term debt
 
$
525,100

 
$
372,950



On September 14, 2014, the Partnership entered into the Amended and Restated Credit Agreement, which was amended by the First Amendment and Incremental Commitment Agreement dated as of September 18, 2015 (as amended, the "Credit Agreement"), which provides for maximum borrowings equal to $750.0 million, with the ability to further increase the borrowing capacity to $900.0 million subject to lender approval. We can elect to have loans under our Credit Agreement bear interest either at a Eurodollar-based rate, plus a margin ranging from 2.00% to 3.25% depending on our total leverage ratio then in effect, or a base rate which is a fluctuating rate per annum equal to the highest of (a) the Federal Funds Rate plus 0.50%, (b) the rate of interest in effect for such day as publicly announced from time to time by Bank of America as its "prime rate," or (c) the Eurodollar Rate plus 1.00% plus a margin ranging from 1.00% to 2.25% depending on the total leverage ratio then in effect. We also pay a commitment fee of 0.50% per annum on the undrawn portion of the revolving loan under the Credit Agreement.

Our obligations under the Credit Agreement are secured by a lien on substantially all of our assets. Advances made under the Credit Agreement are guaranteed on a senior unsecured basis by certain of our subsidiaries (the “Guarantors”). These guarantees are full and unconditional and joint and several among the Guarantors. The terms of the Credit Agreement include covenants that restrict our ability to make cash distributions and acquisitions in some circumstances. The remaining principal balance of loans and any accrued and unpaid interest will be due and payable in full on the maturity date, which is September 5, 2019.

The Credit Agreement contains certain financial covenants, including the requirement that our indebtedness not exceed 4.75 times adjusted consolidated EBITDA for the prior twelve month period adjusted in accordance with the Credit Agreement (except for the current and subsequent two quarters after the consummation of a permitted acquisition, at which time the covenant is increased to 5.25 times adjusted consolidated EBITDA) and a minimum interest coverage ratio test that requires our adjusted consolidated EBITDA to exceed consolidated interest charges by not less than 2.50 times. The financial covenants in our Credit Agreement may limit the amount available to us for borrowing to less than $750.0 million. In addition to the financial covenants described above, the Credit Agreement also contains customary representations and warranties (including those relating to organization and authorization, compliance with laws, absence of defaults, material agreements and litigation) and customary events of default (including those relating to monetary defaults, covenant defaults, cross defaults and bankruptcy events).

For the years ended December 31, 2015, 2014 and 2013, the weighted average interest rate on borrowings under our Credit Agreement was approximately 3.67%, 3.80%, and 4.53%, respectively.

As of December 31, 2015, our consolidated total leverage was 4.56 and our interest coverage ratio was 8.56, which was in compliance with the consolidated total leverage ratio and interest coverage ratio tests in accordance with the financial covenants required in our Credit Agreement. At December 31, 2015 and 2014, letters of credit outstanding under the Credit Agreement were $1.8 million and $1.6 million, respectively. As of December 31, 2015, we had approximately $525.1 million of outstanding borrowings under our $750.0 million Credit Agreement.

As of December 31, 2015, we were in compliance with the covenants included in the Credit Agreement. Our ability to maintain compliance with the  leverage and interest coverage ratios included in the Credit Agreement may be subject to, among other things, the timing and success of initiatives we are pursuing, which may include expansion capital projects, acquisitions, or drop down transactions, as well as the associated financing for such initiatives.  If required, ArcLight Capital Partners, which controls the General Partner of the Partnership, has agreed to provide financial support for the Partnership to maintain compliance with the covenants contained in the Credit Agreement through December 31, 2016.

Other debt

As of December 31, 2015, other debt represents insurance premium financing in the original amount of $3.0 million bearing interest at 3.95% per annum, which is repayable in equal monthly installments of approximately $0.3 million through the third quarter of 2016.
Partners' Capital
Partners' Capital
Partners' Capital and Convertible Preferred Units

Our capital accounts are comprised of approximately 1.3% general partner interest and 98.7% limited partner interests as of December 31, 2015. Our limited partners have limited rights of ownership as provided for under our Partnership Agreement and the right to participate in our distributions. Our General Partner manages our operations and participates in our distributions, including certain incentive distributions pursuant to the incentive distribution rights that are non-voting limited partner interests held by our General Partner. Pursuant to our Partnership Agreement, our General Partner participates in losses and distributions based on its interest. The General Partner's participation in the allocation of losses and distributions are not limited and therefore, such participation can result in a deficit to its respective capital account. As such, allocation of losses and distributions for previous transactions between entities under common control have resulted in a deficit to the General Partner's capital account included in our consolidated balance sheets.

Prior to the conversion of the Series B Units into common units on February 1, 2016, our General Partner held and participated in the distribution on Series B Units with such distributions being made in cash or with paid-in-kind Series B Units at the election of the Partnership. The holders of Series B Units were entitled to vote along with the holders of Limited Partner common units prior to conversion.

HPIP holds and participates on the distributions of Series A-1 Units with such distributions being made in paid-in-kind Series A-1 Units, cash or a combination thereof, at the election of the Board of Directors of our General Partner through the distribution for the earlier of (a) the quarter ended March 31, 2016 or (b) the time in which the Series A-1 Units are converted into common units. The Series A-1 Units are entitled to vote along with Limited Partner common unitholders and such units are currently convertible to Limited Partner common units.

Series A-1 Convertible Preferred Units

On April 15, 2013, the Partnership, our General Partner and AIM Midstream Holdings entered into agreements with HPIP, pursuant to which HPIP i) acquired 90% of our General Partner and all of our subordinated units from AIM Midstream Holdings and ii) contributed the High Point System and $15.0 million in cash to us in exchange for 5,142,857 Series A-1 Units issued by the Partnership as described in Note 2 "Acquisitions and Divestitures". Of the cash consideration paid by HPIP, approximately $2.5 million was used to pay certain transaction expenses of HPIP, and the remaining approximately $12.5 million was used to repay borrowings outstanding under the Partnership's former credit facility. As a result of these transactions, which were also consummated on April 15, 2013, HPIP acquired both control of our General Partner and a majority of our outstanding limited partnership interests. On April 15, 2013, our General Partner entered into the Third Amended & Restated Agreement of Limited Partnership (the "Third Amendment") of the Partnership providing for the creation and designation of the rights, preferences, terms and conditions of the Series A-1 Units.

The Series A-1 Units receive distributions prior to distributions to Partnership common unitholders. The distributions to the Series A-1 Unitholders are equal to the greater of $0.50 per unit or the declared distribution to common unitholders. The Series A-1 Units may be converted into common units on a one-to-one basis, subject to customary anti-dilutive adjustments, at the option of the unitholders on or any time after January 1, 2014.

As a result of the equity offering that closed on September 15, 2015, discussed below, the conversion price of the Series A Units were adjusted from $17.50 to $15.94 in accordance with the terms of the Partnership Agreement so that the holders of those units would maintain their ownership interest on an as-converted basis.

Upon any liquidation and winding up of the Partnership or the sale of substantially all of the assets of the Partnership, the holders of Series A-1 Units generally will be entitled to receive, in preference to the holders of any of the Partnership's other securities, an amount equal to the sum of $15.94 multiplied by the number of Series A-1 Units owned by such holders, plus all accrued but unpaid distributions on such Series A Units.

Prior to the consummation of any recapitalization, reorganization, consolidation, merger, spin-off or other business combination in which the holders of common units are to receive securities, cash or other assets (a "Partnership Event"), we are obligated to make an irrevocable written offer, subject to consummation of the Partnership Event, to each holder of Series A Units to redeem all (but not less than all) of such holder's Series A Units for a price per Series A Unit payable in cash equal to the greater of:

•
the sum of $15.94 and all accrued and accumulated but unpaid distributions for each Series A-1 Unit; or
•
an amount equal to the product of:
i) the number of common units into which each Series A-1 Unit is convertible; and
ii) the sum of:
(A) the cash consideration per common unit to be paid to the holders of common units pursuant to the Partnership Event, plus
(B) the fair market value per common unit of the securities or other assets to be distributed to the holders of the common units pursuant to the Partnership Event.

Upon receipt of such a redemption offer from us, each holder of Series A-1 Units may elect to receive such cash amount or a preferred security issued by the person surviving or resulting from such Partnership Event and containing provisions substantially equivalent to the provisions set forth in the Third Amendment with respect to the Series A-1 Units without material abridgement.
Except as provided in the Third Amendment, the Series A-1 Units have voting rights that are identical to the voting rights of the common units and will vote with the common units as a single class, with each Series A-1 Unit entitled to one vote for each common unit into which such Series A-1 Unit is convertible.

As conversion is at the option of the holder and redemption is contingent upon a future event which is outside the control of the Partnership, the Series A-1 Units have been classified as mezzanine equity in the consolidated balance sheets.

The Partnership executed the Fourth Amendment (the "Fourth Amendment") to the Partnership Agreement related to its outstanding Series A-1 Units which became effective July 24, 2014. As a result of the Fourth Amendment, distributions on Series A-1 Units will be made with paid-in-kind Series A-1 Units, cash or a combination thereof, at the discretion of the Board of Directors, which began with the distribution for the three months ended June 30, 2014 and will continue through the distribution for the quarter ended March 31, 2016. Prior to the Fourth Amendment, the Partnership was required to pay distributions on the Series A-1 Units with a combination of paid-in-kind units and cash.

Series A-2 Convertible Preferred Units

On March 30, 2015 and June 30, 2015, we entered into two Series A-2 Convertible Preferred Unit Purchase Agreements with Magnolia Infrastructure Partners, LLC (an affiliate of HPIP) pursuant to which the Partnership issued, in separate private placements, newly-designated Series A-2 Units (the “Series A-2 Units”) representing limited partnership interests in the Partnership. As a result, the Partnership issued a total of 2,571,430 Series A-2 Units for approximately $45.0 million in aggregate proceeds during the year ended December 31, 2015. The Series A-2 Units will participate in distributions of the Partnership along with common units in a manner identical to the existing Series A-1 Units (together with the Series A-2 Units, the "Series A Units"), with such distributions being made in cash or with paid-in-kind Series A Units at the election of the Board of Directors of our General Partner. To date, the Board of Directors of our General Partner has elected to pay Series A distributions using paid-in-kind Series A Units.

On July 27, 2015, we entered into the Fifth Amendment (the “Fifth Amendment”) to our Partnership Agreement. The Fifth Amendment grants us the right (the “Call Right”) to require the holders of the Series A-2 Units (the “Series A-2 Holders”) to sell, assign and transfer all or a portion of the then outstanding Series A-2 Units to us for a purchase price of $17.50 per Series A-2 Unit (subject to appropriate adjustment for any equity distribution, subdivision or combination of equity interests in the Partnership). We may exercise the Call Right at any time, in connection with our or our affiliate’s acquisition of assets or equity from ArcLightEnergy Partners Fund V, L.P., or one of its affiliates, for a purchase price in excess of $100 million. We may not exercise the Call Right with respect to any Series A-2 Units that a Series A-2 Holder has elected to convert into common units on or prior to the date we have provided notice of our intent to exercise the Call Right, and may not exercise the Call Right if doing so would result in a default under any of our or our affiliates’ financing agreements or obligations.

As a result of the equity offering that closed on September 15, 2015, discussed below, the conversion price of the Series A Units was adjusted to $15.94 in accordance with the terms of the Partnership Agreement so that the holders of those units would maintain their ownership interest on an as-converted basis.

Series B Units

Effective January 31, 2014, the Partnership created and issued 1,168,225 Series B Units to its General Partner in exchange for approximately $30.0 million. The Series B Units participate in distributions of the Board of Directors of our General Partner along with common units, with such distributions being made in cash distributions or with paid-in-kind Series B Units at the election of the Partnership. The Series B Units are entitled to vote along with common unitholders and such units will automatically convert to common units two years after the issuance date. Proceeds from the issuance of the Series B Units were used to partially fund the Lavaca Acquisition.

During 2014, the Board of Directors of our General Partner elected to pay the Series B distributions using paid-in-kind Series B Units. The number of paid-in-kind Series B Units is determined by the quotient of: i) the number of Series B Units outstanding at the record date multiplied by the distribution amount declared to common unit holders ("Series B Unit Distribution Amount"), and ii) the Series B Unit Distribution Amount divided by the original issue price of the Series B Units. The Partnership records the paid-in-kind Series B Units at fair value at the time of issuance. The fair value measurement uses our unit price as a significant input in the determination of the fair value and thus represents a Level 2 measurement as defined by ASC 820. For the year ended December 31, 2015, the Partnership issued 94,923 of paid-in-kind Series B Units with a fair value of $1.4 million. For the year ended December 31, 2014, the Partnership issued 86,461 of paid-in-kind Series B Units with a fair value of $2.2 million.

The Series B Units automatically converted to common units on February 1, 2016.

Equity Restructuring

Effective August 9, 2013, we executed an equity restructuring agreement ("Equity Restructuring") with our General Partner and HPIP. As part of the Equity Restructuring, the Partnership's 4,526,066 subordinated units and previous incentive distribution rights (the "former IDRs," all of which were owned by our General Partner, which is controlled by HPIP) were combined into and restructured as a new class of incentive distribution rights (the "new IDRs"). Upon the issuance of the new IDRs, the subordinated units and former IDRs were canceled. The new IDRs were allocated 85.02% to HPIP and 14.98% to our General Partner. The new IDRs entitle the holders of our incentive distribution rights to receive 48% of any quarterly cash distributions from available cash after the Partnership's common unitholders have received the full minimum quarterly distribution ($0.4125 per unit) for each quarter plus any arrearages from prior quarters. On February 5, 2014, further amendments were made as a result of a settlement such that:
 
•
HPIP and AIM Midstream Holdings amended the LLC Agreement to, among other things, amend the Sharing Percentages (as defined therein) such that HPIP's sharing percentage thereafter is 95% and AIM Midstream Holdings's Sharing Percentage is 5%;

•
HPIP transferred all of the 85.02% of our outstanding new IDRs held by HPIP to our General Partner such that our General Partner owns 100% of the outstanding new IDRs; and

•
we issued to AIM Midstream Holdings a warrant to purchase up to 300,000 common units of the Partnership at an exercise price of $0.01 per common unit (the "Warrant"), which Warrant, among other terms, i) is exercisable at any time on or after February 8, 2014 until the tenth anniversary of February 5, 2014, ii) contains cashless exercise provisions and iii) contains customary anti-dilution and other protections. The Warrant was exercised on February 21, 2014.

Equity Offerings

On October 13, 2015, the Partnership and certain of its affiliates entered into an ATM Equity Offering Sales Agreement (the “Sales Agreement”) with Merrill Lynch, Pierce, Fenner & Smith Incorporated and SunTrust Robinson Humphrey, Inc (each, a "Sales Agent"). Pursuant to the Sales Agreement, the Partnership may issue and sell from time to time, through the Sales Agents, common units having an aggregate offering price of up to $100,000,000.

On September 10, 2015, the Partnership and certain of its affiliates entered into an underwriting agreement with Merrill Lynch, Pierce, Fenner & Smith Incorporated, as representative for the underwriters named therein, providing for the issuance and sale by the Partnership of 7,500,000 common units at a price to the public of $11.31 per common unit. The offering closed on September 15, 2015 and the Partnership used the net proceeds of approximately $81.0 million to fund a portion of the Delta House Investment. In connection with this offering, we completed the issuance of an additional 151,937 common units at a price of $11.31 per unit pursuant to the partial exercise of the underwriters' overallotment option on October 8, 2015 for net proceeds of approximately $1.7 million.

On October 14, 2014, the Partnership acquired Costar from Energy Spectrum Partners VI LP and Costar Midstream Energy, LLC which was funded, in part, with 6,900,000 of common units issued directly to Energy Spectrum and Costar Midstream Energy LLC, which are subject to customary lock-up provisions. In February 2016, the Partnership reached a settlement of certain indemnification claims with the Costar sellers whereby approximately 1,034,483 common units held in escrow were returned to the Partnership.

On July 14, 2014, the Partnership entered into a common unit purchase agreement with certain institutional investors, which was subsequently amended on August 15, 2014, to provide for the sale of 4,622,352 common units representing limited partner interests in the Partnership in a private placement at a price of $25.8075 per common unit (reflecting an adjustment for the Partnership's second quarter distribution of $0.4625 per unit), for cash consideration of $119.3 million.

On January 29, 2014, the Partnership and certain of its affiliates entered into an underwriting agreement (the "Underwriting Agreement") with Barclays Capital Inc. and UBS Securities LLC (the "Underwriters"), providing for the issuance and sale by the Partnership, and the purchase by the Underwriters, of 3,400,000 common units representing limited partner interests in the Partnership at a price to the public of $26.75 per common unit. The Partnership used the net proceeds of $86.9 million to fund a portion of the Lavaca Acquisition.

On December 11, 2013, the Partnership and certain of its affiliates entered into an underwriting agreement (the "Underwriting Agreement") with Barclays Capital Inc. (the "Underwriter"), providing for the issuance and sale by the Partnership, and the purchase by the Underwriter, of 2,568,712 common units representing limited partner interests in the Partnership at a price to the public of $22.47 per common unit. The Partnership used the net proceeds of $54.9 million to fund a portion of the purchase price for the Blackwater Acquisition.

General Partner Units

In connection with the equity offerings discussed above and to maintain its ownership percentage, we received proceeds of $1.9 million from our General Partner as consideration for the issuance of 143,517 additional notional general partner units for the year ended December 31, 2015 and proceeds of $5.7 million for the issuance of 206,810 additional notional general partner units for the year ended December 31, 2014. There were no such contributions in 2013.

Outstanding Units

The numbers of units outstanding were as follows (in thousands):
 
December 31,
 
2015
 
2014
 
2013
Series A convertible preferred units
9,210

 
5,745

 
5,279

Series B convertible units
1,350

 
1,255

 
—

Limited Partner common units
30,427

 
22,670

 
7,414

General Partner units
536

 
392

 
185



Distributions

We made cash distributions as follows (in thousands):
 
Years Ended December 31,
 
2015
 
2014
 
2013
Series A convertible preferred units
$
—

 
$
2,658

 
$
2,375

Limited Partner common units
46,597

 
22,656

 
8,207

Limited Partner subordinated units
—

 
—

 
5,073

General Partner units
1,187

 
333

 
284

General Partners' incentive distribution rights
5,602

 
2,362

 
181

 
$
53,386

 
$
28,009

 
$
16,120


On January 25, 2016, we announced that the Board of Directors of our General Partner declared a quarterly cash distribution of $0.4725 per unit for the fourth quarter ended December 31, 2015, or $1.89 per unit on an annualized basis. The cash distribution was paid on February 12, 2016, to unitholders of record as of the close of business on February 3, 2016. At December 31, 2015, we had accrued $4.4 million for the paid-in-kind Series A Units that were issued in February 2016.

The fair value of the paid-in-kind Series A Unit distributions for all years presented was determined primarily using the market and income approach utilizing significant inputs not observable in the market and thus represent a Level 3 measurement as defined by ASC 820. Primarily using the income approach the fair value estimates for all three years presented were based on i) present value of estimated future contracted distributions, ii) option values ranging from $0.07 per unit to $9.68 per unit using a Black-Scholes model, iii) assumed discount rates of 10.0%, and iv) assumed distribution growth rates of 1.0%.

For the year ended December 31, 2015, the Partnership issued 893,830 of paid-in-kind Series A Units and recorded accrued and paid-in-kind unitholder distributions for Series A Units with a fair value of $17.0 million. For the year ended December 31, 2014, the Partnership issued 466,638 of paid-in-kind Series A Units and recorded accrued and paid-in-kind unitholder distributions for Series A Units with a fair value of $13.2 million. For the year ended December 31, 2013, the Partnership issued 135,705 of paid-in-kind Series A Units and recorded accrued and paid-in-kind unitholder distributions for Series A Units with a fair value of $4.8 million.
Earnings per Unit
Net Income Loss Per Limited and General Partner Unit [Text Block]
Net Income (Loss) per Limited Partner Unit

Net income (loss) is allocated to the General Partner and the limited partners in accordance with their respective ownership percentages, after giving effect to distributions on Series A Units, declared distributions on the Series B Units, limited partner and to the General Partner units, including IDRs. Unvested unit-based payment awards that contain non-forfeitable rights to distributions (whether paid or unpaid) are classified as participating securities and are included in our computation of basic and diluted net income per limited partner unit. Basic and diluted net income (loss) per limited partner unit is calculated by dividing limited partners' interest in net income (loss) by the weighted average number of outstanding limited partner units during the period. We determined basic and diluted net income (loss) per limited partner unit as follows, (in thousands, except per unit amounts):

 
Years Ended December 31,
 
2015
 
2014
 
2013
Net income (loss) from continuing operations
$
(127,375
)
 
$
(97,195
)
 
$
(30,993
)
Net income (loss) attributable to noncontrolling interests
25

 
214

 
633

Net income (loss) from continuing operations attributable to the Partnership
(127,400
)
 
(97,409
)
 
(31,626
)
Less:
 
 
 
 
 
Distributions on Series A preferred units
16,978

 
14,492

 
24,117

Declared distributions on Series B Units
1,373

 
2,220

 
—

General partner's distributions
6,790

 
2,694

 
464

General partner's share in undistributed loss
(2,569
)
 
(1,820
)
 
(1,708
)
Blackwater net loss from continuing operations
—

 
—

 
(716
)
Net income (loss) from continuing operations available to limited Partners
(149,972
)
 
(114,995
)
 
(53,783
)
Net income (loss) from discontinued operations available to Limited Partners
(80
)
 
(603
)
 
(2,051
)
Net income (loss) available to Limited Partners
$
(150,052
)
 
$
(115,598
)
 
$
(55,834
)
 
 
 
 
 
 
Weighted average number of units used in computation of Limited Partners' net income (loss) per unit (basic and diluted)
24,983

 
13,472

 
7,525

 
 
 
 
 
 
Limited Partners' net income (loss) from continuing operations per unit (basic and diluted)
$
(6.00
)
 
$
(8.54
)
 
$
(7.15
)
Limited Partners' net income (loss) from discontinued operations per unit (basic and diluted)
—

 
(0.04
)
 
(0.27
)
Limited Partners' net income (loss) per unit (basic and diluted)
$
(6.00
)
 
$
(8.58
)
 
$
(7.42
)
Long-Term Incentive Plan
Long-Term Incentive Plan
Long-Term Incentive Plan

Our General Partner manages our operations and activities and employs the personnel who provide support to our operations. On November 2, 2009, the Board of Directors of our General Partner adopted a long-term incentive plan for its employees, consultants and directors who perform services for it or its affiliates. On May 25, 2010, the Board of Directors of our General Partner adopted an Amended and Restated Long-Term Incentive Plan. On July 11, 2012, the Board of Directors of our General Partner adopted a Second Amended and Restated Long-Term Incentive Plan that effectively increased available awards by 871,750 units. On November 19, 2015, the Board of Directors of our General Partner approved the Third Amended and Restated Long-Term Incentive Plan, which, subject to unitholder approval, would increase the number of common units authorized for issuance by 6,000,000 common units. On February 11, 2016, the unitholders approved the Third Amended and Restated Long-Term Incentive Plan to increase the number of available awards by 6,000,000 common units. At December 31, 2015, 2014 and 2013, there were 15,484, 688,976 and 855,089 common units, respectively, available for future grant under the LTIP.

All such equity-based awards issued under the LTIP consist of phantom units, DERs or Option Grants. DERs and options have been granted on a limited basis. Future awards, such as options and DERs, may be granted at the discretion of the Compensation Committee and subject to the Board of Directors of our General Partner.

Phantom Unit Awards. Ownership in the awards is subject to forfeiture until the vesting date. The LTIP is administered by the Compensation Committee of the Board of Directors of our General Partner, which at its discretion, may elect to settle such vested phantom units with a number of units equivalent to the fair market value at the date of vesting in lieu of cash. Although our General Partner has the option to settle in cash upon the vesting of phantom units, our General Partner has not historically settled these awards in cash. Under the LTIP, grants issued typically vest in increments of 25% on each grant anniversary date and do not contain any vesting requirements other than continued employment.

In December 2015, the Board of Directors of our General Partner approved a grant of 200,000 phantom units under the LTIP which contains distribution equivalent rights based on the extent to which the Partnership’s Series A Preferred Unitholders receive distributions in cash and will vest in one lump sum installment on the three year anniversary of the date of grant, subject to acceleration in certain circumstances.

The following table summarizes our phantom unit-based awards, in units:

 
 
Years Ended December 31,
 
 
Units
 
Weighted-Average Exercise Price
Outstanding at beginning of period
 
201,132

 
$
19.85

Granted
 
546,329

 
12.25

Forfeited
 
(31,298
)
 
15.62

Vested
 
(146,404
)
 
18.47

Outstanding at end of period
 
569,759

 
$
13.15



The fair value of our phantom units, which are subject to equity classification, is based on the fair value of our units at the grant date. Compensation costs related to these phantom awards for the years ended December 31, 2015, 2014, and 2013 was $3.8 million, $1.5 million and $2.1 million, respectively, and are classified as Equity compensation expense in our consolidated statements of operations and the equity compensation expense in partners' capital on our consolidated balance sheets.

The total fair value of vesting units at the time of vesting was $2.6 million, $1.4 million, and $2.2 million for the years ended December 31, 2015, 2014, and 2013, respectively.

The total compensation cost related to unvested phantom awards not yet recognized at December 31, 2015, 2014, and 2013 was $5.9 million, $3.1 million, and $0.9 million, respectively, and the weighted average period over which this cost is expected to be recognized as of December 31, 2015, is approximately 2.75 years years.

Performance and Service Condition Awards. In November 2015, the Board of Directors of our General Partner modified awards that introduced certain performance and service conditions that are probable, amounting to $2.0 million payable in a variable amount of phantom units awards at the time of grant. As such, these awards are accounted for as liability-based awards and equity-based compensation is to be accrued from the service-inception date through the estimated date of meeting both the performance and service conditions. Compensation costs related to these awards for the years ended December 31, 2015 was $0.5 million. Compensation cost related to unvested awards not yet recognized at December 31, 2015 was $1.5 million.

Option to Purchase Common Units. In December 2015, the Board of Directors of our General Partner approved the grant of an option to purchase 200,000 common units of the Partnership at an exercise price per unit equal to $7.50 (the “Option Grant”). The Option Grant will vest in one lump sum installment on January 1, 2019, subject to acceleration in certain circumstances, and will expire on March 15th of the calendar year following the calendar year in which it vests.

The fair value of each unit-based option award is estimated on the date of grant using a Black-Scholes pricing model that incorporates the assumptions noted in the following table.
Weighted average volatility
47.0
%
Expected dividend yield
26.3
%
Weighted average expected term (in years)
3.5

Weighted average risk-free rate
1.3
%


Estimated expected volatilities were based upon historical volatility of our common units. The expected dividend yield was based on an annualized distribution divided by the closing unit price on the date of grant. The expected term was based on the midpoint between the date of vest and the date of expiration. The risk-free rate was based on the U.S. Treasury yield curve in effect on the date of grant.

Compensation costs related to these awards for the years ended December 31, 2015 was immaterial. Compensation cost related to unvested awards not yet recognized at December 31, 2015 was $0.1 million.

The following table summarizes our Option Grant awards, in units:

 
 
Year Ended December 31, 2015
 
 
Units
 
Weighted-Average Exercise Price
Outstanding at beginning of period
 
—

 
$
—

Granted
 
200,000

 
7.50

Forfeited
 
—

 
—

Vested
 
—

 
—

Outstanding at end of period
 
200,000

 
$
7.50

Post-Employment Benefits
Post-Employment Benefits
Postretirement Benefits

One of the Partnership’s subsidiaries has a contributory postretirement benefit plan that provides medical, dental and life insurance benefits for qualified retirees. Plan obligations totaled $0.6 million and $0.7 million at December 31, 2015 and 2014, respectively, while plan assets totaled $1.8 million and $1.7 million as of those dates. Plan assets are invested primarily in fixed income securities. Net periodic benefit plan costs, which are included in Direct operating expenses in our consolidated statements of operations, are less than $(0.1) million for the years ended December 31, 2015, 2014 and 2013. The Partnership expects that annual benefit payments will be made from plan assets in the future and will be less than $0.1 million per year.
Income Tax (Notes)
Income Tax Disclosure [Text Block]
 Income Taxes

With the exception of certain subsidiaries in our Terminals Segment, the Partnership is not subject to U.S. federal or state income taxes as such income taxes are generally borne by our unitholders through the allocation of our taxable income (loss) to them. The State of Texas does impose a franchise tax that is assessed on the portion of our taxable margin which is apportioned to Texas.

Our income tax (expense) benefit for the years ended December 31, 2015, 2014 and 2013 is as follows:
 
Years Ended December 31,
 
2015
 
2014
 
2013
Current income tax benefit (expense)
$
—

 
$
(10
)
 
$
—

Deferred income tax benefit (expense)
(1,134
)
 
(547
)
 
495

 
 
 
 
 
 
Effective income tax rate
0.9
%
 
0.6
%
 
1.6
%


A reconciliation of our expected income tax (expense) benefit calculated at the U.S. federal statutory rate of 34% to our actual tax (expense) for the years ended December 31, 2015, 2014 and 2013 is as follows:

 
Years Ended December 31,
 
2015
 
2014
 
2013
Net loss before income tax benefit (expense)
$
(126,241
)
 
$
(96,638
)
 
$
(31,488
)
US Federal statutory tax rate
34
%
 
34
%
 
34
%
Federal income tax benefit at statutory rate
42,922

 
32,857

 
10,706

Reconciling items:
 
 
 
 
 
    Partnership loss not subject to income tax
(43,812
)
 
(33,216
)
 
(10,296
)
    Income not subject to corporate-level tax
—

 
—

 
222

    State and local tax benefit (expense)
(103
)
 
(159
)
 
71

    Other
(141
)
 
(39
)
 
(208
)
Income tax benefit (expense)
$
(1,134
)
 
$
(557
)
 
$
495


The Partnership’s deferred tax assets and liabilities as of December 31, 2015 and 2014 are summarized below:
 
December 31,
 
2015
 
2014
Deferred tax assets:
 
 
 
    Net operating loss carryforwards
$
7,570

 
$
4,173

    Other
493

 
213

    Total deferred tax assets
8,063

 
4,386

Deferred tax liabilities:
 
 
 
    Property, plant and equipment
13,889

 
9,112

    Intangible assets
—

 
387

    Total deferred tax liabilities
13,889

 
9,499

Deferred income tax liability, net
$
(5,826
)
 
$
(5,113
)


As of December 31, 2015, certain subsidiaries in our Terminals Segment had net operating losses for federal income tax purposes of approximately $19.3 million which begin to expire in 2028. The annual utilization of the federal net operating losses may be limited by changes in control of the subsidiaries which occurred in 2012 and 2013.

We recognize the tax benefits from uncertain tax positions if it is more likely than not that the position will be sustained on examination by the taxing authorities. As of December 31, 2015, we have not recognized tax benefits from uncertain tax positions.

The preparation of our income tax returns requires the use of management's estimates and interpretations which may be subjected to review by the respective taxing authorities and may result in an assessment of additional taxes, penalties and interest. Tax years subsequent to 2009 remain subject to examination by federal and state taxing authorities.
Commitments and Contingencies
Commitments and Contingencies
Commitments and Contingencies

Legal proceedings

We are not currently party to any pending litigation or governmental proceedings, other than ordinary routine litigation incidental to our business. While the ultimate impact of any proceedings cannot be predicted with certainly, our management believes that the resolution of any of our pending proceeds will not have a material adverse effect on our financial condition or results of operations.

Environmental matters

We are subject to federal and state laws and regulations relating to the protection of the environment. Environmental risk is inherent to natural gas pipeline, NGL and crude pipelines and operations, as well as terminal operations and we could, at times, be subject to environmental cleanup and enforcement actions. We attempt to manage this environmental risk through appropriate environmental policies and practices to minimize any impact our operations may have on the environment.

Regulatory matters

On October 8, 2014, American Midstream (Midla), LLC ("Midla") reached an agreement in principle with its customers regarding the interstate pipeline that traverses Louisiana and Mississippi in order to provide continued service to its customers while addressing safety concerns with the existing pipeline.

On December 11, 2014, Midla filed a Stipulation and Agreement (the "Midla Agreement") which resolved all of the related outstanding issues.

On April 16, 2015, the FERC approved the Midla Agreement allowing Midla to retire the existing 1920s vintage pipeline and replace it with a new pipeline from Winnsboro, Louisiana to Natchez, Mississippi (the “Midla-Natchez Line”) to serve existing residential, commercial, and industrial customers. Under the Midla Agreement, customers not served by the new Midla-Natchez Line will be connected to other interstate or intrastate pipelines, other gas distribution systems, or offered conversion to propane service. On June 29, 2015, the Partnership filed with the FERC for authorization to construct the Midla-Natchez pipeline, which was approved on December 17, 2015. Construction is expected to commence in the first half of 2016 with service beginning in late 2016. Under the Midla Agreement, Midla plans to execute long-term agreements seeking to recover its investment in the Midla-Natchez Line.

Commitments and contractual obligations

Future non-cancelable commitments related to the following contractual obligations as of December 31, 2015, are presented below (in thousands):
 
 
Operating leases and service contracts
 
Asset Retirement Obligation
 
Total
2016
 
$
3,721

 
$
6,822

 
$
10,543

2017
 
2,286

 
—

 
2,286

2018
 
1,173

 
—

 
1,173

2019
 
1,345

 
—

 
1,345

2020
 
1,006

 
—

 
1,006

Thereafter
 
1,537

 
28,549

 
30,086

 
 
$
11,068

 
$
35,371

 
$
46,439



For the years ended December 31, 2015, 2014 and 2013, total expenses related to operating leases, land site leases and right-of-way agreements were $12.0 million, $5.8 million, and $1.1 million, respectively.
Related-Party Transactions
Related-Party Transactions
Related-Party Transactions

Employees of our General Partner are assigned to work for the Partnership or affiliates of our General Partner. Where directly attributable, the costs of all compensation, benefits expenses and employer expenses for these employees are charged directly by our General Partner to American Midstream, LLC, which, in turn, charges the appropriate subsidiary or affiliate. Our General Partner does not record any profit or margin for the administrative and operational services charged to us. During the years ended December 31, 2015, 2014, and 2013, administrative payroll and operational services expenses of $28.7 million, $22.6 million and $14.2 million, respectively, were charged to the Partnership by our General Partner.

For the years ended December 31, 2015 and 2014, our General Partner incurred approximately $1.5 million and $0.9 million, respectively, of costs related to business development compensation that were funded by the Partnership. There were no such costs for the year ended December 31, 2013. As of December 31, 2015, the Partnership has been reimbursed for these costs. For the years ended December 31, 2015, 2014 and 2013, our General Partner also incurred approximately less than $0.1 million, $0.1 million and $0.8 million of costs associated with other business development activities, respectively. If the business development activities result in a project that will be pursued and funded by the Partnership, we will reimburse our General Partner for the business development costs related to that project and record those costs in our consolidated statements of operations.

During the year ended December 31, 2015, the Partnership and an affiliate of HPIP entered into arrangements under which the affiliate reimbursed the Partnership for right-of-ways purchased on the affiliate's behalf for approximately $3.9 million. During the year ended December 31, 2015, the Partnership purchased certain equipment from an affiliate for $0.3 million.

During the second quarter of 2014, the Partnership and an affiliate of its General Partner entered into a Management Service Fee arrangement under which the affiliate pays a monthly fee to reimburse the Partnership for administrative expenses incurred on the affiliate's behalf. For the years ended December 31, 2015 and 2014, the Partnership recognized $1.4 million and $0.9 million, respectively, in management fee income that has been recorded as a reduction to Selling, general and administrative expenses.

As of December 31, 2015, the Partnership had $3.8 million due to our General Partner, which has been recorded in Accrued expenses and other current liabilities and relates primarily to compensation. This payable is generally settled on a quarterly basis. As of December 31, 2014, the Partnership had $0.7 million due to our General Partner and $0.8 million due from affiliates of our General Partner, which are recorded in Accrued expenses and other current liabilities and Other current assets, respectively.

Other Transactions with Affiliates

On March 30, 2015 and June 30, 2015, we entered into two Series A-2 Convertible Preferred Unit Purchase Agreements with Magnolia Infrastructure Partners, LLC (an affiliate of HPIP) pursuant to which the Partnership issued, in separate private placements, newly-designated Series A-2 Units (the “Series A-2 Units”) representing limited partnership interests in the Partnership. As a result, the Partnership issued a total of 2,571,430 Series A-2 Units for approximately $45.0 million in aggregate proceeds during the year ended December 31, 2015. See Note 14 "Partners' Capital and Convertible Preferred Units" for more information.

In April 2013, the High Point System, along with $15.0 million in cash, was contributed to us by HPIP in exchange for 5,142,857 Series A Units. Of the cash consideration paid by HPIP, approximately $2.5 million was used to pay certain transaction expenses of HPIP, and the remaining approximately $12.5 million was used to repay borrowings outstanding under the Partnership's former credit facility.

In January 2014, in connection with the acquisition of the Lavaca System, the Partnership issued 1,168,225 Series B Units to our General Partner. The net proceeds related to the issuance was $30.0 million.

In connection with the Blackwater Acquisition in December 2013, our General Partner contributed the net assets of Blackwater which were recorded at their historical book value of $22.7 million for consideration of $63.9 million, of which $27.7 million was accounted for as a cash distribution to the General Partner. The consideration also included 125,500 limited partner units which were accounted for as a non-cash distribution to the General Partner at a fair value of $3.1 million. See Note 2 "Acquisitions and Divestitures" for more information.
Reporting Segments
Reporting Segments
Reportable Segments

Our operations are located in the United States and are organized into three reportable segments: i) Gathering and Processing, ii) Transmission and iii) Terminals.

Gathering and Processing

Our Gathering and Processing segment provides "wellhead-to-market" services to producers of natural gas and crude oil, which include transporting raw natural gas from the wellhead through gathering systems, treating the raw natural gas, processing raw natural gas to separate the NGLs from the natural gas, fractionating NGLs, and selling or delivering pipeline-quality natural gas and NGLs to various markets and pipeline systems.

Transmission

Our Transmission segment transports and delivers natural gas from producing wells, receipt points or pipeline interconnects for shippers and other customers, including local distribution companies, or LDCs, utilities and industrial, commercial and power generation customers.

Terminals

Our Terminals segment provides above-ground storage services at our marine terminals that support various commercial customers, including commodity brokers, refiners and chemical manufacturers to store a range of products, including petroleum products, distillates, chemicals and agricultural products.

These segments are monitored separately by management for performance and are consistent with the Partnership's internal financial reporting. These segments have been identified based on the differing products and services, regulatory environment and the expertise required for these operations. Gross margin is a performance measure utilized by management to monitor the results of each segment.
 
The following tables set forth our segment information for the periods indicated (in thousands):

 
Year Ended December 31, 2015
 
Gathering
and
Processing
 
Transmission
 
Terminals
 
Total
Revenue
$
173,597

 
$
43,682

 
$
17,755

 
$
235,034

Gain (loss) on commodity derivatives, net
1,324

 
—

 
—

 
1,324

Total revenue
174,921

 
43,682

 
17,755

 
236,358

Operating expenses:
 
 
 
 
 
 
 
Purchases of natural gas, NGL's and condensate
97,580

 
8,303

 
—

 
105,883

Direct operating expenses
39,189

 
13,720

 
6,640

 
59,549

Selling, general and administrative expenses
 
 
 
 
 
 
27,232

Equity compensation expense
 
 
 
 
 
 
3,774

Depreciation, amortization and accretion expense
 
 
 
 
 
 
38,014

Total operating expenses
 
 
 
 
 
 
234,452

Gain (loss) on sale of assets, net
 
 
 
 
 
 
(3,011
)
Loss on impairment of goodwill
 
 
 
 
 
 
(118,592
)
Interest expense
 
 
 
 
 
 
(14,745
)
Earnings in unconsolidated affiliates
 
 
 
 
 
 
8,201

Income tax (expense) benefit
 
 
 
 
 
 
(1,134
)
Income (loss) from discontinued operations, net of tax
 
 
 
 
 
 
(80
)
Net income (loss)
 
 
 
 
 
 
(127,455
)
Less: Net income (loss) attributable to noncontrolling interests
 
 
 
 
 
 
25

Net income (loss) attributable to the Partnership
 
 
 
 
 
 
$
(127,480
)
 
 
 
 
 
 
 
 
Segment gross margin (a)
$
76,865

 
$
35,301

 
$
11,115

 
$
123,281


 
Year Ended December 31, 2014
 
Gathering
and
Processing
 
Transmission
 
Terminals
 
Total
Revenue
$
203,616

 
$
88,189

 
$
15,504

 
$
307,309

Gain (loss) on commodity derivatives, net
1,091

 
—

 
—

 
1,091

Total revenue
204,707

 
88,189

 
15,504

 
308,400

Operating expenses:
 
 
 
 
 
 
 
Purchases of natural gas, NGL's and condensate
152,690

 
45,262

 
—

 
197,952

Direct operating expenses
23,783

 
15,577

 
6,342

 
45,702

Selling, general and administrative expenses
 
 
 
 
 
 
23,103

Equity compensation expense
 
 
 
 
 
 
1,536

Depreciation, amortization and accretion expense
 
 
 
 
 
 
28,832

Total operating expenses
 
 
 
 
 
 
297,125

Gain (loss) on sale of assets, net
 
 
 
 
 
 
(122
)
Loss on impairment of property, plant and equipment
 
 
 
 
 
 
(99,892
)
Interest expense
 
 
 
 
 
 
(7,577
)
Other income (expense)
 
 
 
 
 
 
(670
)
Earnings in unconsolidated affiliates
 
 
 
 
 
 
348

Income tax (expense) benefit
 
 
 
 
 
 
(557
)
Income (loss) from discontinued operations, net of tax
 
 
 
 
 
 
(611
)
Net income (loss)
 
 
 
 
 
 
(97,806
)
Less: Net income (loss) attributable to noncontrolling interests
 
 
 
 
 
 
214

Net income (loss) attributable to the Partnership
 
 
 
 
 
 
$
(98,020
)
 
 
 
 
 
 
 
 
Segment gross margin (a)
$
50,817

 
$
42,828

 
$
9,162

 
$
102,807


 
Year Ended December 31, 2013
 
Gathering
and
Processing
 
Transmission
 
Terminals (b)
 
Total
Revenue
$
205,179

 
$
79,041

 
$
9,831

 
$
294,051

Gain (loss) on commodity derivatives, net
28

 
—

 
—

 
28

Total revenue
205,207

 
79,041

 
9,831

 
294,079

Operating expenses:
 
 
 
 
 
 
 
Purchases of natural gas, NGL's and condensate
168,574

 
46,479

 
—

 
215,053

Direct operating expenses
14,574

 
13,259

 
4,403

 
32,236

Selling, general and administrative expenses
 
 
 
 
 
 
19,079

Equity compensation expense
 
 
 
 
 
 
2,094

Depreciation, amortization and accretion expense
 
 
 
 
 
 
30,002

Total operating expenses
 
 
 
 
 
 
298,464

Gain (loss) on involuntary conversion of property, plant and equipment
 
 
 
 
 
 
343

Loss on impairment of property, plant and equipment
 
 
 
 
 
 
(18,155
)
Interest expense
 
 
 
 
 
 
(9,291
)
Income tax (expense) benefit
 
 
 
 
 
 
495

Income (loss) from discontinued operations, net of tax
 
 
 
 
 
 
(2,413
)
Net income (loss)
 
 
 
 
 
 
(33,406
)
Less: Net income (loss) attributable to noncontrolling interests
 
 
 
 
 
 
633

Net income (loss) attributable to the Partnership
 
 
 
 
 
 
$
(34,039
)
 
 
 
 
 
 
 
 
Segment gross margin (a)
$
36,985

 
$
32,408

 
$
5,428

 
$
74,821


 
December 31,
 
2015
 
2014
Segment assets:
 
 
 
Gathering and Processing
$
572,824

 
$
686,395

Transmission
133,870

 
132,767

Terminals
84,449

 
68,094

Other (c)
100,153

 
26,302

Total assets
$
891,296

 
$
913,558


(a)
Segment gross margin for our Gathering and Processing segment consists of revenue less purchases of natural gas, NGLs and condensate and COMA. Segment gross margin for our Transmission segment consists of revenue, less purchases of natural gas and COMA. Segment gross margin for our Terminals segment consists of revenue, less direct operating expenses. Gross margin consists of the sum of the segment gross margin amounts for each of these segments. As an indicator of our operating performance, gross margin should not be considered an alternative to, or more meaningful than, net income or cash flow from operations as determined in accordance with GAAP. Our gross margin may not be comparable to a similarly titled measure of another company because other entities may not calculate gross margin in the same manner.
(b)
Terminals segment amounts are for the period from April 15, 2013 to December 31, 2013.
(c)
Other assets not allocable to segments consist of investment in unconsolidated affiliate, corporate leasehold improvements, and other assets.

For a definition of gross margin and a reconciliation to its most directly comparable financial measure calculated and presented in accordance with GAAP and a discussion of how we use gross margin to evaluate our operating performance, please read Item 7. "Management's Discussion and Analysis, How We Evaluate Our Operations."

The following table summarizes the percentage of revenue earned from those customers in each segment that exceed 10% of the Partnership's consolidated segment's revenue for the each of the periods presented below:

 
Years Ended December 31,
 
2015
 
2014
 
2013
Gathering and Processing:
 
 
 
 
 
Customer A
12
%
 
33
%
 
43
%
Customer B
—
%
 
12
%
 
19
%
Customer J
12
%
 
—
%
 
—
%
Other
76
%
 
55
%
 
38
%
Total
100
%
 
100
%
 
100
%
Transmission:
 
 
 
 
 
Customer C
—
%
 
43
%
 
39
%
Customer D
16
%
 
16
%
 
16
%
Customer K
19
%
 
—
%
 
—
%
Other
65
%
 
41
%
 
45
%
Total
100
%
 
100
%
 
100
%
Terminals:
 
 
 
 
 
Customer F
13
%
 
19
%
 
20
%
Customer B
13
%
 
20
%
 
17
%
Customer G
21
%
 
15
%
 
16
%
Customer H
—
%
 
11
%
 
13
%
Customer I
13
%
 
—
%
 
—
%
Other
40
%
 
35
%
 
34
%
Total
100
%
 
100
%
 
100
%
Quarterly Financial Data (Notes)
Quarterly Financial Information [Text Block]
Quarterly Financial Data (Unaudited)

Summarized unaudited quarterly financial data for 2015 and 2014 are as follows (in thousands, except per unit amounts):
 
 
First
Quarter
 
Second
Quarter
 
Third
Quarter
 
Fourth
Quarter (b)
Year Ended December 31, 2015
 
 
 
 
 
 
 
Total revenues
$
64,609

 
$
67,509

 
$
55,641

 
$
48,599

Gross margin (a)
33,776

 
32,304

 
29,134

 
28,067

Operating income (loss)
3,434

 
1,867

 
(1,523
)
 
(123,475
)
Net income (loss) from continuing operations
835

 
(2,002
)
 
(4,574
)
 
(121,634
)
Income (loss) from discontinued operations, net of tax
5

 
(31
)
 
(53
)
 
(1
)
Net income (loss) attributable to noncontrolling interest
14

 
32

 
34

 
(55
)
Net income (loss) attributable to the Partnership
826

 
(2,065
)
 
(4,661
)
 
(121,580
)
General Partner's Interest in net income (loss)
10

 
(25
)
 
(60
)
 
(1,570
)
Limited Partners' Interest in net income (loss)
$
816

 
$
(2,040
)
 
$
(4,601
)
 
$
(120,010
)
 
 
 
 
 
 
 
 
Limited Partners' income (loss) per unit:
 
 
 
 
 
 
 
Income (loss) from continuing operations
$
(0.19
)
 
$
(0.35
)
 
$
(0.48
)
 
$
(4.16
)
Income (loss) from discontinued operations
—

 
—

 
—

 
—

Net income (loss)
$
(0.19
)
 
$
(0.35
)
 
$
(0.48
)
 
$
(4.16
)
Year Ended December 31, 2014
 
 
 
 
 
 
 
Total revenues
$
80,238

 
$
77,680

 
$
70,305

 
$
80,177

Gross margin (a)
23,081

 
22,167

 
21,332

 
36,227

Operating income (loss)
2,450

 
734

 
(290
)
 
(91,633
)
Net income (loss) from continuing operations
558

 
(1,095
)
 
(2,397
)
 
(94,261
)
Income (loss) from discontinued operations, net of tax
(50
)
 
(506
)
 
(26
)
 
(29
)
Net income (loss) attributable to noncontrolling interest
108

 
66

 
33

 
7

Net income (loss) attributable to the Partnership
400

 
(1,667
)
 
(2,456
)
 
(94,297
)
General Partner's Interest in net income (loss)
7

 
(22
)
 
(32
)
 
(1,232
)
Limited Partners' Interest in net income (loss)
$
393

 
$
(1,645
)
 
$
(2,424
)
 
$
(93,065
)
 
 
 
 
 
 
 
 
Limited Partners' income (loss) per unit:
 
 
 
 
 
 
 
Income (loss) from continuing operations
$
(0.31
)
 
$
(0.55
)
 
$
(0.58
)
 
$
(4.98
)
Income (loss) from discontinued operations
(0.01
)
 
(0.04
)
 
—

 
—

Net income (loss)
$
(0.32
)
 
$
(0.59
)
 
$
(0.58
)
 
$
(4.98
)
 
(a)
For a definition of gross margin and a reconciliation to its most directly comparable financial measure calculated and presented in accordance with GAAP and a discussion of how we use gross margin to evaluate our operating performance, please read Item 7. "Management's Discussion and Analysis, How We Evaluate Our Operations."
(b)
In the fourth quarter of 2015, we recognized a Loss on impairment of goodwill of $118.6 million. In the fourth quarter of 2014, we recognized a Loss on impairment of property, plant and equipment of $99.9 million.
Organization and Basis of Presentation (Policies)
Nature of business 

American Midstream Partners, LP (the "Partnership"), was formed on August 20, 2009 as a Delaware limited partnership for the purpose of operating, developing and acquiring a diversified portfolio of midstream energy assets. The Partnership's general partner, American Midstream GP, LLC (the "General Partner"), is 95% owned by High Point Infrastructure Partners, LLC ("HPIP") and 5% owned by AIM Midstream Holdings, LLC. We hold our assets primarily in a number of wholly owned limited liability companies, two limited partnerships and a corporation. Our capital accounts consist of notional general partner units and limited partner interests.

Nature of business

We are engaged in the business of gathering, treating, processing, and transporting natural gas; gathering, transporting, storing, treating and fractionating NGLs; gathering, storing and transporting crude oil and condensates; and storing specialty chemical products, all through our ownership and operation of twelve gathering systems, five processing facilities, three fractionation facilities, three marine terminal sites, three interstate pipelines, five intrastate pipelines and one crude oil pipeline. We also own a 66.7% non-operated interest in Main Pass Oil Gathering Company ("MPOG"), a crude oil gathering and processing system; a 50% undivided, non-operated interest in the Burns Point Plant, a natural gas processing plant; a 46% non-operated interest in Mesquite, an off-spec condensate fractionation project; and a 12.9% non-operated indirect interest in the Delta House floating production system and related pipeline infrastructure ("Delta House"). Our primary assets, which are strategically located in Alabama, Georgia, Louisiana, Mississippi, North Dakota, Tennessee, Texas and the Gulf of Mexico, provide critical infrastructure that links producers of natural gas, crude oil, NGLs, condensate and specialty chemicals to numerous intermediate and end-use markets. We currently operate more than 3,000 miles of pipelines that gather and transport over 1 Bcf/d of natural gas and operate approximately 1.8 million barrels of storage capacity across three marine terminal sites.

Basis of presentation 
Basis of presentation

We have prepared the accompanying consolidated financial statements in accordance with accounting principles generally accepted in the United States of America ("GAAP").

The results of operations for acquisitions accounted for as business combinations have been included in the consolidated financial statements since their respective acquisition dates. See Note 2 "Acquisitions and Divestitures" for further information.
Transactions Between Entities Under Common Control 
Transactions Between Entities Under Common Control
 
We may enter into transactions with our General Partner and affiliates whereby we receive a contribution of midstream assets or subsidiaries in exchange for consideration from the Partnership. We account for the net assets received using the historical book value of the asset or subsidiary being contributed or transferred as these are transactions between entities under common control. Our historical financial statements may be revised to include the results attributable to the assets contributed from our General Partner as if we owned such assets for all periods presented by the Partnership since either the change in control of our General Partner, effective April 15, 2013 or later.
Consolidation policy 
Consolidation policy

The accompanying consolidated financial statements include accounts of American Midstream Partners, LP, and its controlled subsidiaries. All significant inter-company accounts and transactions have been eliminated in the preparation of the accompanying consolidated financial statements.
Equity Method Investments 
Investment in Unconsolidated Affiliates

Equity investments in which the Partnership exercises significant influence, but does not control and is not the primary beneficiary, are accounted for using the equity method and are reported in Investment in unconsolidated affiliates in the accompanying consolidated balance sheets.

The Partnership believes the equity method is an appropriate means for it to recognize increases or decreases measured by GAAP in the economic resources underlying the investments. Regular evaluation of these investments is appropriate to evaluate any potential need for impairment. The Partnership uses evidence of a loss in value to identify if an investment has declined in value, other than a temporary decline.

The Partnership accounts for its 66.7% non-operated interest in MPOG, its 46.0% non-operated interest in Mesquite and its 12.9% non-operated indirect interest in Delta House under the equity method.
Use of estimates 
Use of estimates

When preparing consolidated financial statements in conformity with GAAP, management must make estimates and assumptions based on information available at the time. These estimates and assumptions affect the reported amounts of assets, liabilities, revenues and expenses, as well as the disclosures of contingent assets and liabilities as of the date of the financial statements. Estimates and assumptions are based on information available at the time such estimates and assumptions are made. Adjustments made with respect to the use of these estimates and assumptions often relate to information not previously available. Uncertainties with respect to such estimates and assumptions are inherent in the preparation of financial statements. Estimates and assumptions are used in, among other things, i) estimating unbilled revenues, product purchases and operating and general and administrative costs, ii) developing fair value assumptions, including estimates of future cash flows and discount rates, iii) analyzing long-lived assets, goodwill and intangible assets for possible impairment, iv) estimating the useful lives of assets and v) determining amounts to accrue for contingencies, guarantees and indemnifications. Actual results, therefore, could differ materially from estimated amounts.
Cash and cash equivalents 
Cash and cash equivalents

We consider all highly liquid investments with an original maturity of three months or less at the date of purchase to be cash equivalents. The carrying value of cash and cash equivalents approximates fair value because of the short term to maturity of these investments.
Allowance for doubtful accounts 
Allowance for doubtful accounts

We establish provisions for losses on accounts receivable when we determine that we will not collect all or part of an outstanding balance. Collectability is reviewed regularly and an allowance is established or adjusted, as necessary, using the specific identification method. As of December 31, 2015 and 2014, the Partnership recorded no allowances for losses on accounts receivable.
Operational balancing agreements and natural gas imbalances 
Operational balancing agreements and natural gas imbalances

To facilitate deliveries of natural gas and provide for operational flexibility, we have operational balancing agreements in place with other interconnecting pipelines. These agreements ensure that the volume of natural gas a shipper schedules for transportation between two interconnecting pipelines equals the volume actually delivered. If natural gas moves between pipelines in volumes that are more or less than the volumes the shipper previously scheduled, a natural gas imbalance is created. The imbalances are settled through periodic cash payments or repaid in-kind through future receipt or delivery of natural gas. Natural gas imbalances are recorded as gas imbalances and classified within Other current assets or Other current liabilities on our consolidated balance sheets at cost which approximates fair value.
Derivative financial instruments 
Derivative financial instruments

Our net income (loss) and cash flows are subject to volatility stemming from changes in interest rates on our variable rate debt, commodity prices and fractionation margins (the relative difference between the price we receive from NGL sales and the corresponding cost of natural gas purchases). In an effort to manage the risks to unitholders, we use a variety of derivative financial instruments including swaps, collars and interest rate caps to create offsetting positions to specific commodity or interest rate exposures. In accordance with the authoritative accounting guidance, we record all derivative financial instruments in our consolidated balance sheets at fair value as current and long-term assets or liabilities on a net basis by counterparty. We record changes in the fair value of our derivative financial instruments in our consolidated statements of operations as follows:

•
Commodity-based derivatives: "Total revenue"
•
Corporate interest rate derivatives: "Interest expense"

Our formal hedging program provides a control structure and governance for our hedging activities specific to identified risks and time periods, which are subject to the approval and monitoring by the Board of Directors of our General Partner. We employ derivative financial instruments in connection with an underlying asset, liability or anticipated transaction, and we do not use derivative financial instruments for speculative or trading purposes.

The price assumptions we use to value our derivative financial instruments can affect net income (loss) for each period. We use published market price information where available, or quotations from over-the-counter, or OTC, market makers to find executable bids and offers. The valuations also reflect the potential impact of conditions, including credit risk of our counterparties. The amounts reported in our consolidated financial statements change quarterly as these valuations are revised to reflect actual results, changes in market conditions or other factors, many of which are beyond our control.
Fair value measurements 
Fair value measurements

We apply the authoritative accounting provisions for measuring fair value of our derivative instruments and disclosures associated with our outstanding indebtedness. We define fair value as an exit price representing the expected amount we would receive when selling an asset or pay to transfer a liability in an orderly transaction with market participants at the measurement date.

We use various assumptions and methods in estimating the fair values of our financial instruments. The carrying amounts of cash and cash equivalents, accounts receivable and accounts payable approximated their fair value due to the short-term maturity of these instruments. The carrying amount of our various credit facilities approximate fair value, because the interest rates on these facilities are variable.

We employ a hierarchy which prioritizes the inputs we use to measure recurring fair value into three distinct categories based upon whether such inputs are observable in active markets or unobservable. We classify assets and liabilities in their entirety based on the lowest level of input that is significant to the fair value measurement. Our methodology for categorizing assets and liabilities that are measured at fair value pursuant to this hierarchy gives the highest priority to unadjusted quoted prices in active markets and the lowest level to unobservable inputs as outlined below:

•
Level 1 – Inputs represent unadjusted quoted prices in active markets for identical assets or liabilities;
•
Level 2 – Inputs include quoted prices for similar assets and liabilities in active markets that are either directly or indirectly observable; and
•
Level 3 – Inputs are unobservable and considered significant to fair value measurement.

We utilize a mid-market pricing convention, or the "market approach," for valuation for assigning fair value to our derivative assets and liabilities. Our credit exposure for over-the-counter derivatives is directly with our counterparty and continues until the maturity or termination of the contracts. As appropriate, valuations are adjusted for various factors such as credit and liquidity considerations.
Property, plant and equipment 
Property, plant and equipment

We capitalize expenditures related to property, plant and equipment that have a useful life greater than one year for assets purchased or constructed; existing assets that are replaced, improved, or the useful lives of which have been extended; and all land, regardless of cost. Maintenance and repair costs, including any planned major maintenance activities, are expensed as incurred.

We record property, plant, and equipment at its original cost, which we depreciate on a straight-line basis over its estimated useful life. Our determination of the useful lives of property, plant and equipment requires us to make various assumptions, including the supply of and demand for hydrocarbons in the markets served by our assets, normal wear and tear of the facilities, and the extent and frequency of maintenance programs. We record depreciation using the group method of depreciation, which is commonly used by pipelines, utilities and similar assets.

We classify long-lived assets to be disposed of through sales that meet specific criteria as held for sale. We cease depreciating those assets effective on the date the asset is classified as held for sale. We record those assets at the lower of their carrying value or the estimated fair value less the cost to sell. Until the assets are disposed of, an estimate of the fair value is re-determined when related events or circumstances change.
Impairment of long lived Assets 
Impairment of long lived Assets

We evaluate the recoverability of our property, plant and equipment and intangible assets with definite lives when events or circumstances indicate we may not recover the carrying amount of the assets. We continually monitor our operations, the market, and business environment to identify indicators that could suggest an asset or asset group may not be recoverable. We evaluate the asset or asset group for recoverability by estimating the undiscounted future cash flows expected to be derived from their use and disposition. These cash flow estimates require us to make projections and assumptions for many years into the future for pricing, demand, competition, operating cost, contract renewals, and other factors. An asset or asset group is considered impaired when the estimated undiscounted cash flows are less than the carrying amount. In that event, an impairment loss is recognized to the extent that the carrying amount of the asset or asset group exceeds its fair value as determined by quoted market prices in active markets or present value techniques. The determination of fair values using present value techniques requires us to make projections and assumptions regarding future cash flows and weighted average cost of capital. Any changes we make to these projections and assumptions could result in significant revisions to our evaluation of the recoverability of our property, plant and equipment and the recognition of an impairment loss in our consolidated statements of operations.
Goodwill and intangible assets 
Goodwill and intangible assets

We record goodwill for the excess of the cost of an acquisition over the fair value of the net assets of the acquired business. Goodwill is not amortized but is reviewed for impairment at least annually or more frequently if an event or change in circumstance indicates that an impairment may have occurred. We first assess qualitative factors to evaluate whether it is more likely than not that an impairment has occurred and it is therefore necessary to perform the two-step goodwill impairment test. If the two-step goodwill impairment test indicates that the goodwill is impaired, an impairment loss is recorded.

We record the estimated fair value of acquired customer contracts, relationships and dedicated acreage agreements as intangible assets. These intangible assets have definite lives and are subject to amortization on a straight-line basis over their economic lives, currently ranging between 10 years and 30 years. We assess intangible assets for impairment together with related underlying long-lived assets whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable.
Deferred financing costs 
Deferred financing costs

Costs incurred in connection with our revolving credit facility are deferred and charged to interest expense over the term of the related credit arrangement. Gains or losses on debt repurchase and debt extinguishment include any associated unamortized deferred financing costs.
Asset retirement obligations (AROs) 
Asset retirement obligations ("AROs")

AROs are legal obligations associated with the retirement of tangible long-lived assets that result from the asset's acquisition, construction, development and operation. An ARO is initially measured at its estimated fair value. Upon initial recognition, we also record an increase to the carrying amount of the related long-lived asset. We depreciate the asset using the straight-line method over the period during which it is expected to provide benefits. After initial recognition, we revise the ARO to reflect the passage of time and for changes in the estimated amount or timing of cash flows.

We have legal obligations requiring us to decommission our offshore pipeline systems at retirement. In certain rate jurisdictions, we are permitted to include annual charges for removal costs in the regulated cost of service rates we charge our customers. Additionally, legal obligations exist for a minority of our offshore right-of-way agreements due to requirements or landowner options to compel us to remove the pipe at final abandonment. Sufficient data exists with certain onshore pipeline systems to reasonably estimate the cost of abandoning or retiring a pipeline system. However, in some cases, there is insufficient information to reasonably determine the timing and/or method of settlement of estimating the fair value of the asset retirement obligation. In these cases, the asset retirement obligation cost is considered indeterminate because there is no data or information that can be derived from past practice, industry practice, management's experience, or the asset's estimated economic life. The useful lives of most pipeline systems are primarily derived from available supply resources and ultimate consumption of those resources by end users. Variables can affect the remaining lives of the assets which preclude us from making a reasonable estimate of the asset retirement obligation. Indeterminate asset retirement obligation costs will be recognized in the period in which sufficient information exists to reasonably estimate potential settlement dates and methods.
Commitments, contingencies and environmental liabilities 
Commitments, contingencies and environmental liabilities

We expense or capitalize, as appropriate, expenditures for ongoing compliance with environmental regulations that relate to past or current operations. We expense amounts we incur from the remediation of existing environmental contamination caused by past operations that do not benefit future periods by preventing or eliminating future contamination. We record liabilities for environmental matters when assessments indicate that remediation efforts are probable and the costs can be reasonably estimated. Estimates of environmental liabilities are based on currently available facts, existing technology and presently enacted laws and regulation taking into consideration the likely effects of inflation and other factors. These amounts also take into account our prior experience in remediating contaminated sites, other companies' clean-up experience and data released by government organizations. Our estimates are subject to revision in future periods based on actual cost or new information. We evaluate recoveries from insurance coverage separately from the liability and, when recovery is probable, we record an asset separately from the associated liability in our consolidated financial statements.

We recognize liabilities for other commitments and contingencies when, after fully analyzing the available information, we determine it is either probable that an asset has been impaired or that a liability has been incurred and the amount of impairment or loss can be reasonably estimated. When a range of probable loss can be estimated, we accrue the most likely amount or if no amount is more likely than another, we accrue the minimum of the range of probable loss. We expense legal costs associated with loss contingencies as such costs are incurred.
Noncontrolling interests 
Noncontrolling interests

Noncontrolling interests represent the minority interest holders' proportionate share of the equity of the respective systems. Noncontrolling interests are adjusted for the minority interest holders' proportionate share of the earnings or losses. Management reports noncontrolling interest in the Chatom system in the financial statements pursuant to paragraph ASC 810-10-65-1. The 7.8% noncontrolling interest is held by non-affiliated working interest owners
Revenue recognition and the estimation of revenues and cost of purchases 
Revenue recognition and the estimation of revenues and cost of purchases

We recognize revenue when all of the following criteria are met: i) persuasive evidence of an exchange arrangement exists, ii) delivery has occurred or services have been rendered, iii) the price is fixed or determinable, and iv) collectability is reasonably assured. We record revenue and cost of product sold on a gross basis for those transactions where we act as the principal and take title to natural gas, crude oil, NGLs or condensates that are purchased for resale. When our customers pay us a fee for providing a service such as gathering, treating, transportation or storage, we record those fees separately in revenues.
Equity-based compensation 
Equity-based compensation

We award equity-based compensation to management, non-management employees and directors under our Long-Term Incentive Plan ("LTIP"), which provides for the issuance of options, unit appreciation rights, restricted units, phantom units, other unit-based awards, unit awards or replacement awards, as well as tandem Distribution Equivalent Rights ("DERs"). Compensation expense is measured by the fair value of the award at the date of grant as determined by management. Compensation expense is recognized in Equity compensation expense over the requisite service period of each award.
Income taxes 
Income taxes

The Partnership is not a taxable entity for U.S. federal income tax purposes or for the majority of states that impose an income tax. Taxes on our net income are generally borne by our unitholders through the allocation of taxable income. American Midstream Blackwater, LLC, a subsidiary of the Partnership, owns a subsidiary that has operations which are subject to both federal and state income taxes. We account for income taxes of that subsidiary using an asset and liability approach for financial accounting and reporting of income taxes. If it is more than likely that a deferred tax asset will not be realized, a valuation allowance is recognized.

Certain tax expense results from the enactment of laws by the State of Texas that apply to entities organized as partnerships and is included in Income tax (expense) benefit in our consolidated statements of operations. The Texas margin tax is computed on our taxable margin apportioned to Texas annually.

Net income (loss) for financial statement purposes may differ significantly from taxable income (loss) allocable to unitholders as a result of differences between the financial reporting and income tax bases of our assets and liabilities and the taxable income allocation requirement under our Partnership Agreement. The aggregate difference in the basis of our net assets for financial and tax reporting purposes cannot be readily determined because information regarding each partner's tax attributes in us is not available.
Accumulated other comprehensive income (loss) 
Accumulated other comprehensive income (loss)

Accumulated other comprehensive income (loss) is comprised solely of adjustments related to the Partnership's postretirement benefit plan.

Limited partners' net income (loss) per unit 
Limited partners' net income (loss) per unit

We compute earnings per unit using the two-class method. The two-class method requires that securities that meet the definition of a participating security be considered for inclusion in the computation of basic earnings per unit. Under the two-class method, earnings per unit is calculated as if all of the earnings for the period were distributed under the terms of the Partnership Agreement, regardless of whether the General Partner has discretion over the amount of distributions to be made in any particular period, whether those earnings would actually be distributed during a particular period from an economic or practical perspective, or whether the General Partner has other legal or contractual limitations on its ability to pay distributions that would prevent it from distributing all of the earnings for a particular period.

The two-class method does not impact our overall net income or other financial results; however, in periods in which aggregate net income exceeds our aggregate distributions for such period, it will have the impact of reducing net income per limited partner unit. This result occurs as a larger portion of our aggregate earnings, as if distributed, is allocated to the incentive distribution rights of the General Partner, even though we make distributions on the basis of available cash and not earnings. In periods in which our aggregate net income does not exceed our aggregate distributions for such period, the two-class method does not have any impact on our calculation of earnings per limited partner unit.
Recent Accounting Pronouncements Policies (Policies)
New Accounting Pronouncements
Recent Accounting Pronouncements

In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09, Revenue from Contracts with Customers (Topic 606), which amends the existing accounting standards for revenue recognition. The standard requires an entity to recognize revenue in a manner that depicts the transfer of goods or services to customers at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2015-14 was subsequently issued and deferred the effective date to annual reporting periods beginning after December 15, 2017, including interim reporting periods within that period. We are currently evaluating the method of adoption and impact this standard will have on our consolidated financial statements and related disclosures.

In February 2015, the FASB issued ASU No. 2015-02, Consolidation - Amendments to the Consolidation Analysis, which amends the current consolidation guidance. The amendments affect both the variable interest entity ("VIE") and voting interest entity ("VOE") consolidation models.  The standard is effective for public reporting entities in the fiscal periods beginning after December 15, 2015, early adoption is permitted.  The Partnership has evaluated the impact of this standard on its consolidated financial statements and determined it will not have a material impact.

In April 2015, the FASB issued ASU No. 2015-03, Simplifying the Presentation of Debt Issuance Costs. This amendment requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. ASU 2015-03 is effective for fiscal years beginning after December 15, 2015, including interim periods therein, and is applied retrospectively. Early adoption is permitted for financial statements that have not been previously issued. ASU 2015-15, Presentation and Subsequent Measurement of Debt Issue Costs Associated with Line of Credit Arrangements, was subsequently issued to address the absence of authoritative guidance for debt issuance costs related to line-of-credit arrangements and states that the Securities and Exchange Commission ("SEC") staff will not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement. Given the Partnership's debt issuance costs relate to its Credit Agreement (as defined in Note 13 "Debt Obligations"), the Partnership is not required to alter its current accounting for such costs.

In April 2015, the FASB issued ASU No. 2015-05, Intangibles — Goodwill and Other — Internal-Use Software (Subtopic 350-40), which assists entities in evaluating the accounting for fees paid by a customer in a cloud computing arrangement by providing guidance as to whether an arrangement includes the sales or license of software. The amendment will be effective prospectively for reporting periods beginning on or after December 15, 2015, and early adoption is permitted. The Partnership has evaluated the impact of this standard on its financial statements and determined it will not have a material impact.

In April 2015, the FASB issued ASU No. 2015-06, Earnings Per Share (Topic 260).  This guidance clarifies the process for updating historical earnings per unit disclosures when a drop-down transaction occurs between entities under common control.  Pursuant to the amendment, the earnings (losses) of a transferred business before the date of a dropdown transaction should be allocated entirely to the general partner. Additionally, the previously reported earnings per unit measure presented in the historical financial statements would not change as a result of the drop-down transaction.  ASU 2015-06 is effective for annual reporting periods beginning after December 15, 2015, and for interim periods within those fiscal years.  Early adoption is permitted.  The Partnership has evaluated this guidance and determined it will not have a material impact.

In September 2015, the FASB issued ASU No. 2015-16, Business Combinations (Topic 805). This amendment requires that an acquirer recognize adjustments to provisional amounts that are identified during the measurement period in the reporting period in which the adjustment amounts are determined. ASU 2015-16 is effective for fiscal years beginning after December 15, 2015, including interim periods within those fiscal years. Early adoption is permitted for financial statements that have not been issued. The Partnership has evaluated this guidance and determined it is consistent with our policy and historical presentation.

In November 2015, the FASB issued ASU 2015-17, Income Taxes (Topic 740). This amendment requires that deferred tax liabilities and assets be classified as noncurrent. ASU 2015-17 is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early adoption is permitted. The Partnership has evaluated this guidance and elected to adopt this amendment for the fiscal year ended December 31, 2015. As such, the Partnership’s deferred tax liabilities and assets have been classified as noncurrent in the consolidated balance sheets as of December 31, 2015, and 2014.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). This amendment requires the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous GAAP. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. We are currently evaluating the method of adoption and impact this standard will have on our consolidated financial statements and related disclosures.
Acquisitions (Tables)
Schedule of business acquisitions 
The following table summarizes the fair value of consideration transferred to acquire Costar and the allocation of that amount to the assets acquired, liabilities assumed and the noncontrolling interest for the Costar Acquisition based upon their respective fair values as of the acquisition date (in thousands).
Fair value of consideration transferred (in thousands):
 
Cash
$
258,001

Limited partner common units
147,296

Total fair value of consideration
$
405,297

Schedule of recognized identified assets acquired and liabilities assumed 
The following table summarizes the final allocation of the purchase price to the assets acquired in the Lavaca Acquisition based upon their respective fair values as of the acquisition date (in thousands):
Property, plant and equipment:
 
Land
$
2

Pipelines
58,737

Equipment
753

Total property, plant and equipment
59,492

Intangible assets
21,350

Goodwill
23,567

Total cash consideration
$
104,409

Fair Value of assets acquired, liabilities assumed and noncontrolling interest (in thousands):
 
Working capital
$
8,152

Property, plant and equipment:
 
Processing plants
$
48,357

Pipelines
128,799

Land
1,244

Buildings
682

Equipment
9,827

Construction in progress
16,146

Total property, plant and equipment
205,055

Investment in unconsolidated affiliate
11,884

Intangible assets:
 
Customer relationships
53,400

Dedicated acreage
32,000

Goodwill
95,025

Noncontrolling interest
(219
)
 
$
405,297

Unaudited pro forma consolidated information of the partnership, adjusted for the acquisition of the Costar assets 
The following unaudited pro forma summary presents consolidated financial information for the Partnership as if the Costar acquisition had occurred on January 1, 2013 (in thousands):
 
Years Ended December 31,
 
2014
 
2013
Revenue
$
435,133

 
$
448,748

Net loss
(101,237
)
 
(30,672
)
Limited partners' net loss per unit
(6.15
)
 
(3.82
)
Discontinued Operations (Tables)
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures [Table Text Block]
The following table presents the revenue, expense and (loss) gain from discontinued operations associated with the assets classified as held for sale for the years ended December 31, 2015, 2014, and 2013 (in thousands, except per unit amounts):

 
Years Ended December 31,
 
2015
 
2014
 
2013
Revenue
$
74

 
$
474

 
$
2,084

Expense
(196
)
 
(658
)
 
(2,361
)
Impairment
—

 
(673
)
 
(2,400
)
Loss on sale of assets
(150
)
 
(87
)
 
(75
)
Income tax benefit
192

 
333

 
339

Income (loss) from discontinued operations, net of tax
$
(80
)
 
$
(611
)
 
$
(2,413
)
Limited partners' net income (loss) per unit from discontinued operations (basic and diluted)
$
—

 
$
(0.04
)
 
$
(0.27
)
Concentration of Credit Risk and Trade Accounts Receivable (Tables)
Percentage of revenue earned from major customers
The following table summarizes those customers who accounted for more than 10% of the Partnership's consolidated revenue for the each of the last three years:

 
Years Ended December 31,
 
2015
 
2014
 
2013
Customer A
10
%
 
22
%
 
28
%
Customer B
—
%
 
—
%
 
13
%
Customer C
—
%
 
12
%
 
12
%
Customer D
—
%
 
10
%
 
10
%
Other
90
%
 
56
%
 
37
%
Total
100
%
 
100
%
 
100
%
The following table summarizes the percentage of revenue earned from those customers in each segment that exceed 10% of the Partnership's consolidated segment's revenue for the each of the periods presented below:

 
Years Ended December 31,
 
2015
 
2014
 
2013
Gathering and Processing:
 
 
 
 
 
Customer A
12
%
 
33
%
 
43
%
Customer B
—
%
 
12
%
 
19
%
Customer J
12
%
 
—
%
 
—
%
Other
76
%
 
55
%
 
38
%
Total
100
%
 
100
%
 
100
%
Transmission:
 
 
 
 
 
Customer C
—
%
 
43
%
 
39
%
Customer D
16
%
 
16
%
 
16
%
Customer K
19
%
 
—
%
 
—
%
Other
65
%
 
41
%
 
45
%
Total
100
%
 
100
%
 
100
%
Terminals:
 
 
 
 
 
Customer F
13
%
 
19
%
 
20
%
Customer B
13
%
 
20
%
 
17
%
Customer G
21
%
 
15
%
 
16
%
Customer H
—
%
 
11
%
 
13
%
Customer I
13
%
 
—
%
 
—
%
Other
40
%
 
35
%
 
34
%
Total
100
%
 
100
%
 
100
%
Other Current Assets (Tables)
Schedule of other current assets
Other current assets consists of the following (in thousands):
 
December 31,
 
2015
 
2014
Prepaid insurance—current portion
$
3,948

 
$
4,162

Restricted cash
—

 
6,475

Other prepaid amounts
2,866

 
758

Other current assets
3,280

 
4,159

 
$
10,094

 
$
15,554



Restricted cash of $6.5 million as of December 31, 2014 consisted of a cash-backed letter of credit related to Costar operations that the Partnership was contractually obligated to maintain after the Costar Acquisition. The Partnership was released from this obligation in January 2015. Other current assets primarily consist of natural gas imbalances and amounts due from related parties.
Derivatives (Tables)
Fair value associated with commodity derivative instruments 
As of December 31, 2015 and 2014, the value associated with our commodity derivatives, interest rate swap and weather derivative were recorded in our consolidated balance sheets, under the captions as follows (in thousands):
 
 
Gross Risk Management Assets
 
Gross Risk Management Liabilities
 
Net Risk Management Assets (Liabilities)
Balance Sheet Classification
 
December 31, 2015
 
December 31, 2014
 
December 31, 2015
 
December 31, 2014
 
December 31, 2015
 
December 31, 2014
Current
 
$
365

 
$
688

 
$
—

 
$
—

 
$
365

 
$
688

Noncurrent
 
—

 
—

 
—

 
—

 
—

 
—

Total assets
 
$
365

 
$
688

 
$
—

 
$
—

 
$
365

 
$
688

 
 
 
 
 
 
 
 
 
 
 
 
 
Current
 
$
—

 
$
—

 
$
—

 
$
(215
)
 
$
—

 
$
(215
)
Noncurrent
 
—

 
—

 
—

 
—

 
—

 
—

Total liabilities
 
$
—

 
$
—

 
$
—

 
$
(215
)
 
$
—

 
$
(215
)

Realized and unrealized gains (losses) with commodity and interst rate derivative instruments 
For the years ended December 31, 2015, 2014 and 2013, the realized and unrealized gains (losses) associated with our commodity, interest rate and weather derivative instruments were recorded in our consolidated statements of operations, under the captions as follows (in thousands):
 
 
Realized
 
Unrealized
2015
 

Gain (loss) on commodity derivatives, net
 
$
1,610

 
$
(286
)
Interest expense
 
(240
)
 
215

Direct operating expenses
 
(913
)
 
—

Total
 
$
457

 
$
(71
)
2014
 
 
 
 
Gain (loss) on commodity derivatives, net
 
$
735

 
$
356

Interest expense
 
(433
)
 
239

Direct operating expenses
 
(1,035
)
 
—

Total
 
$
(733
)
 
$
595

2013
 
 
 
 
Gain (loss) on commodity derivatives, net
 
$
1,069

 
$
(1,041
)
Interest expense
 
(207
)
 
(454
)
Direct operating expenses
 
(662
)
 
—

Total
 
$
200

 
$
(1,495
)
Fair Value Measurement (Tables)
Fair value of financial instruments
Fair Value of Financial Instruments

The following table sets forth by level within the fair value hierarchy, our commodity derivative instruments and interest rate swap, included as part of Risk management assets and Risk management liabilities within the consolidated balance sheets, that were measured at fair value on a recurring basis as of December 31, 2015 and 2014 (in thousands):

 
Carrying
Amount
 
Estimated Fair Value of the Asset (Liability)
 
Level 1
 
Level 2
 
Level 3
 
Total
Commodity derivative instruments, net
 
 
 
 
 
 
 
 
 
December 31, 2015
$
—

 
$
—

 
$
—

 
$
—

 
$
—

December 31, 2014
286

 
—

 
286

 
—

 
286

Interest rate swap
 
 
 
 
 
 
 
 
 
December 31, 2015
$
—

 
$
—

 
$
—

 
$
—

 
$
—

December 31, 2014
(215
)
 
—

 
(215
)
 
—

 
(215
)

The unamortized portion of the premium paid to enter the weather derivative described in Note 6 "Derivatives," is included within Risk management assets on the consolidated balance sheets but is not included in the above table as it is recorded at amortized cost, not fair value.
Property, Plant and Equipment, Net (Tables)
Property, plant, and equipment, net
Property, plant and equipment, net, as of December 31, 2015 and 2014, were as follows (in thousands):
 
 
Useful Life
(in years)
 
December 31,
2015
 
December 31,
2014
Land
N/A
 
$
5,282

 
$
5,282

Construction in progress
N/A
 
46,045

 
77,550

Buildings and improvements
4 to 40
 
9,864

 
6,855

Processing and treating plants
8 to 40
 
97,784

 
80,837

Pipelines and compressors
3 to 40
 
554,400

 
476,997

Storage
20 to 40
 
58,394

 
38,151

Equipment
5 to 20
 
22,207

 
12,345

Total property, plant and equipment
 
 
793,976

 
698,017

Accumulated depreciation
 
 
(145,963
)
 
(115,835
)
Property, plant and equipment, net
 
 
$
648,013

 
$
582,182

Goodwill and Intangible assets (Tables)
Schedule of Finite-Lived Intangible Assets [Table Text Block]
Intangible assets, net, consist of the following (in thousands):
 
December 31,
 
2015
 
2014
Gross carrying amount:
 
 
 
    Customer contracts
$
12,101

 
$
12,101

    Customer relationships
53,400

 
53,400

    Dedicated acreage
53,350

 
53,350

 
$
118,851

 
$
118,851

Accumulated amortization:
 
 
 
    Customer contracts
$
(12,101
)
 
$
(11,110
)
    Customer relationships
(3,124
)
 
(553
)
    Dedicated acreage
(2,661
)
 
(882
)
 
$
(17,886
)
 
$
(12,545
)
Net carrying amount:
 
 
 
    Customer contracts
$
—

 
$
991

    Customer relationships
50,276

 
52,847

    Dedicated acreage
50,689

 
52,468

 
$
100,965

 
$
106,306

Investment in unconsolidated affiliates (Tables)
Investments in and Advances to Affiliates [Table Text Block] 
The following table presents the activity in the Partnership's equity investments (in thousands):

 
 
MPOG
 
Mesquite
 
Pinto/Delta House
 
Total
 
 
66.7%
 
46%
 
12.9%
 
 
Balances at December 31, 2013
$
—

 
$
—

 
$
—

 
$
—

 
Initial investment
12,000

 
11,884

 
—

 
23,884

 
Earnings in unconsolidated affiliates
348

 
—

 
—

 
348

 
Distributions
(1,980
)
 
—

 
—

 
(1,980
)
Balances at December 31, 2014
$
10,368

 
$
11,884

 
$
—

 
$
22,252

 
Initial investment
—

 
—

 
65,703

 
65,703

 
Earnings in unconsolidated affiliates
731

 
—

 
7,470

 
8,201

 
Contributions
—

 
6,713

 
—

 
6,713

 
Distributions
(3,920
)
 
—

 
(16,648
)
 
(20,568
)
Balances at December 31, 2015
$
7,179

 
$
18,597

 
$
56,525

 
$
82,301

Equity Method Investments [Table Text Block] 
The following tables present the summarized combined financial information for the Partnership's equity investments (amounts represent 100% of investee financial information):

 
Years Ended December 31,
Balance Sheets:
2015
 
2014
Current assets
$
2,086

 
$
2,196

Non-current assets
288,617

 
62,635

Current liabilities
366

 
398

Non-current liabilities
23,617

 
22,307


 
Years Ended December 31,
Income Statements:
2015
 
2014
 
2013
Total revenue
$
37,724

 
$
3,847

 
$
—

Operating expense
3,375

 
1,722

 
—

Net income
29,437

 
510

 
—

Accrued Expenses and Other Current Liabilities (Tables)
Schedule of accrued expenses and other current liabilities
Accrued expenses and other current liabilities were as follows (in thousands):

 
 
December 31,
 
 
2015
 
2014
Current portion of asset retirement obligation
 
$
6,822

 
$
—

Accrued capital expenditures
 
3,984

 
17,134

Accrued expenses
 
3,178

 
4,560

Due to related parties
 
3,894

 
659

Gas imbalances payable
 
413

 
1,055

Other
 
6,744

 
2,392

 
 
$
25,035

 
$
25,800

Asset Retirement Obligation (Tables)
Schedule of reconciliation of the beginning and ending aggregate carrying amount of ARO liabilities
The following table presents activity in the Partnership's asset retirement obligations (in thousands):
 
Years Ended December 31,
 
2015
 
2014
Beginning asset retirement obligation
$
34,645

 
$
34,636

Liabilities assumed
—

 
248

Expenditures
(91
)
 
(1,030
)
Accretion expense
817

 
791

Total ending asset retirement obligation
35,371

 
34,645

Less: current portion
6,822

 
—

Long-term asset retirement obligation
$
28,549

 
$
34,645

Debt Obligations (Tables)
Outstanding borrowings under the credit facility
Our outstanding borrowings under the credit facility were (in thousands):
 
 
December 31,
 
 
2015
 
2014
Revolving credit facility
 
$
525,100

 
$
372,950

Other debt
 
2,338

 
2,908

Total debt
 
527,438

 
375,858

Less: current portion
 
2,338

 
2,908

Long-term debt
 
$
525,100

 
$
372,950

Partners' Capital (Tables)
Schedule for number of units outstanding 
The numbers of units outstanding were as follows (in thousands):
 
December 31,
 
2015
 
2014
 
2013
Series A convertible preferred units
9,210

 
5,745

 
5,279

Series B convertible units
1,350

 
1,255

 
—

Limited Partner common units
30,427

 
22,670

 
7,414

General Partner units
536

 
392

 
185

Distributions Made to Limited Partner, by Distribution 
We made cash distributions as follows (in thousands):
 
Years Ended December 31,
 
2015
 
2014
 
2013
Series A convertible preferred units
$
—

 
$
2,658

 
$
2,375

Limited Partner common units
46,597

 
22,656

 
8,207

Limited Partner subordinated units
—

 
—

 
5,073

General Partner units
1,187

 
333

 
284

General Partners' incentive distribution rights
5,602

 
2,362

 
181

 
$
53,386

 
$
28,009

 
$
16,120


Earnings per Unit (Tables)
Schedule of Earnings Per Share, Basic and Diluted, Per General and Limited Partner Unit, Including Two Class Method [Table Text Block]
We determined basic and diluted net income (loss) per limited partner unit as follows, (in thousands, except per unit amounts):

 
Years Ended December 31,
 
2015
 
2014
 
2013
Net income (loss) from continuing operations
$
(127,375
)
 
$
(97,195
)
 
$
(30,993
)
Net income (loss) attributable to noncontrolling interests
25

 
214

 
633

Net income (loss) from continuing operations attributable to the Partnership
(127,400
)
 
(97,409
)
 
(31,626
)
Less:
 
 
 
 
 
Distributions on Series A preferred units
16,978

 
14,492

 
24,117

Declared distributions on Series B Units
1,373

 
2,220

 
—

General partner's distributions
6,790

 
2,694

 
464

General partner's share in undistributed loss
(2,569
)
 
(1,820
)
 
(1,708
)
Blackwater net loss from continuing operations
—

 
—

 
(716
)
Net income (loss) from continuing operations available to limited Partners
(149,972
)
 
(114,995
)
 
(53,783
)
Net income (loss) from discontinued operations available to Limited Partners
(80
)
 
(603
)
 
(2,051
)
Net income (loss) available to Limited Partners
$
(150,052
)
 
$
(115,598
)
 
$
(55,834
)
 
 
 
 
 
 
Weighted average number of units used in computation of Limited Partners' net income (loss) per unit (basic and diluted)
24,983

 
13,472

 
7,525

 
 
 
 
 
 
Limited Partners' net income (loss) from continuing operations per unit (basic and diluted)
$
(6.00
)
 
$
(8.54
)
 
$
(7.15
)
Limited Partners' net income (loss) from discontinued operations per unit (basic and diluted)
—

 
(0.04
)
 
(0.27
)
Limited Partners' net income (loss) per unit (basic and diluted)
$
(6.00
)
 
$
(8.58
)
 
$
(7.42
)
Long-Term Incentive Plan (Tables)
Schedule of Share-based Compensation Restricted Stock and Restricted Stock Units Activity 
The following table summarizes our phantom unit-based awards, in units:

 
 
Years Ended December 31,
 
 
Units
 
Weighted-Average Exercise Price
Outstanding at beginning of period
 
201,132

 
$
19.85

Granted
 
546,329

 
12.25

Forfeited
 
(31,298
)
 
15.62

Vested
 
(146,404
)
 
18.47

Outstanding at end of period
 
569,759

 
$
13.15

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions 
The fair value of each unit-based option award is estimated on the date of grant using a Black-Scholes pricing model that incorporates the assumptions noted in the following table.
Weighted average volatility
47.0
%
Expected dividend yield
26.3
%
Weighted average expected term (in years)
3.5

Weighted average risk-free rate
1.3
%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value 
The following table summarizes our Option Grant awards, in units:

 
 
Year Ended December 31, 2015
 
 
Units
 
Weighted-Average Exercise Price
Outstanding at beginning of period
 
—

 
$
—

Granted
 
200,000

 
7.50

Forfeited
 
—

 
—

Vested
 
—

 
—

Outstanding at end of period
 
200,000

 
$
7.50

Income Tax (Tables)
Schedule of Deferred Tax Assets and Liabilities [Table Text Block] 
The Partnership’s deferred tax assets and liabilities as of December 31, 2015 and 2014 are summarized below:
 
December 31,
 
2015
 
2014
Deferred tax assets:
 
 
 
    Net operating loss carryforwards
$
7,570

 
$
4,173

    Other
493

 
213

    Total deferred tax assets
8,063

 
4,386

Deferred tax liabilities:
 
 
 
    Property, plant and equipment
13,889

 
9,112

    Intangible assets
—

 
387

    Total deferred tax liabilities
13,889

 
9,499

Deferred income tax liability, net
$
(5,826
)
 
$
(5,113
)
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] 
Our income tax (expense) benefit for the years ended December 31, 2015, 2014 and 2013 is as follows:
 
Years Ended December 31,
 
2015
 
2014
 
2013
Current income tax benefit (expense)
$
—

 
$
(10
)
 
$
—

Deferred income tax benefit (expense)
(1,134
)
 
(547
)
 
495

 
 
 
 
 
 
Effective income tax rate
0.9
%
 
0.6
%
 
1.6
%
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] 
A reconciliation of our expected income tax (expense) benefit calculated at the U.S. federal statutory rate of 34% to our actual tax (expense) for the years ended December 31, 2015, 2014 and 2013 is as follows:

 
Years Ended December 31,
 
2015
 
2014
 
2013
Net loss before income tax benefit (expense)
$
(126,241
)
 
$
(96,638
)
 
$
(31,488
)
US Federal statutory tax rate
34
%
 
34
%
 
34
%
Federal income tax benefit at statutory rate
42,922

 
32,857

 
10,706

Reconciling items:
 
 
 
 
 
    Partnership loss not subject to income tax
(43,812
)
 
(33,216
)
 
(10,296
)
    Income not subject to corporate-level tax
—

 
—

 
222

    State and local tax benefit (expense)
(103
)
 
(159
)
 
71

    Other
(141
)
 
(39
)
 
(208
)
Income tax benefit (expense)
$
(1,134
)
 
$
(557
)
 
$
495


Commitments and Contingencies (Tables)
Future non-cancelable commitments related to certain contractual obligations 
Future non-cancelable commitments related to the following contractual obligations as of December 31, 2015, are presented below (in thousands):
 
 
Operating leases and service contracts
 
Asset Retirement Obligation
 
Total
2016
 
$
3,721

 
$
6,822

 
$
10,543

2017
 
2,286

 
—

 
2,286

2018
 
1,173

 
—

 
1,173

2019
 
1,345

 
—

 
1,345

2020
 
1,006

 
—

 
1,006

Thereafter
 
1,537

 
28,549

 
30,086

 
 
$
11,068

 
$
35,371

 
$
46,439

Total expenses related to operating leases, asset retirement obligations, land site leases and right-of-way agreements 
The following table presents activity in the Partnership's asset retirement obligations (in thousands):
 
Years Ended December 31,
 
2015
 
2014
Beginning asset retirement obligation
$
34,645

 
$
34,636

Liabilities assumed
—

 
248

Expenditures
(91
)
 
(1,030
)
Accretion expense
817

 
791

Total ending asset retirement obligation
35,371

 
34,645

Less: current portion
6,822

 
—

Long-term asset retirement obligation
$
28,549

 
$
34,645

Reporting Segments (Tables)
Segment information for the periods 
The following tables set forth our segment information for the periods indicated (in thousands):

 
Year Ended December 31, 2015
 
Gathering
and
Processing
 
Transmission
 
Terminals
 
Total
Revenue
$
173,597

 
$
43,682

 
$
17,755

 
$
235,034

Gain (loss) on commodity derivatives, net
1,324

 
—

 
—

 
1,324

Total revenue
174,921

 
43,682

 
17,755

 
236,358

Operating expenses:
 
 
 
 
 
 
 
Purchases of natural gas, NGL's and condensate
97,580

 
8,303

 
—

 
105,883

Direct operating expenses
39,189

 
13,720

 
6,640

 
59,549

Selling, general and administrative expenses
 
 
 
 
 
 
27,232

Equity compensation expense
 
 
 
 
 
 
3,774

Depreciation, amortization and accretion expense
 
 
 
 
 
 
38,014

Total operating expenses
 
 
 
 
 
 
234,452

Gain (loss) on sale of assets, net
 
 
 
 
 
 
(3,011
)
Loss on impairment of goodwill
 
 
 
 
 
 
(118,592
)
Interest expense
 
 
 
 
 
 
(14,745
)
Earnings in unconsolidated affiliates
 
 
 
 
 
 
8,201

Income tax (expense) benefit
 
 
 
 
 
 
(1,134
)
Income (loss) from discontinued operations, net of tax
 
 
 
 
 
 
(80
)
Net income (loss)
 
 
 
 
 
 
(127,455
)
Less: Net income (loss) attributable to noncontrolling interests
 
 
 
 
 
 
25

Net income (loss) attributable to the Partnership
 
 
 
 
 
 
$
(127,480
)
 
 
 
 
 
 
 
 
Segment gross margin (a)
$
76,865

 
$
35,301

 
$
11,115

 
$
123,281


 
Year Ended December 31, 2014
 
Gathering
and
Processing
 
Transmission
 
Terminals
 
Total
Revenue
$
203,616

 
$
88,189

 
$
15,504

 
$
307,309

Gain (loss) on commodity derivatives, net
1,091

 
—

 
—

 
1,091

Total revenue
204,707

 
88,189

 
15,504

 
308,400

Operating expenses:
 
 
 
 
 
 
 
Purchases of natural gas, NGL's and condensate
152,690

 
45,262

 
—

 
197,952

Direct operating expenses
23,783

 
15,577

 
6,342

 
45,702

Selling, general and administrative expenses
 
 
 
 
 
 
23,103

Equity compensation expense
 
 
 
 
 
 
1,536

Depreciation, amortization and accretion expense
 
 
 
 
 
 
28,832

Total operating expenses
 
 
 
 
 
 
297,125

Gain (loss) on sale of assets, net
 
 
 
 
 
 
(122
)
Loss on impairment of property, plant and equipment
 
 
 
 
 
 
(99,892
)
Interest expense
 
 
 
 
 
 
(7,577
)
Other income (expense)
 
 
 
 
 
 
(670
)
Earnings in unconsolidated affiliates
 
 
 
 
 
 
348

Income tax (expense) benefit
 
 
 
 
 
 
(557
)
Income (loss) from discontinued operations, net of tax
 
 
 
 
 
 
(611
)
Net income (loss)
 
 
 
 
 
 
(97,806
)
Less: Net income (loss) attributable to noncontrolling interests
 
 
 
 
 
 
214

Net income (loss) attributable to the Partnership
 
 
 
 
 
 
$
(98,020
)
 
 
 
 
 
 
 
 
Segment gross margin (a)
$
50,817

 
$
42,828

 
$
9,162

 
$
102,807


 
Year Ended December 31, 2013
 
Gathering
and
Processing
 
Transmission
 
Terminals (b)
 
Total
Revenue
$
205,179

 
$
79,041

 
$
9,831

 
$
294,051

Gain (loss) on commodity derivatives, net
28

 
—

 
—

 
28

Total revenue
205,207

 
79,041

 
9,831

 
294,079

Operating expenses:
 
 
 
 
 
 
 
Purchases of natural gas, NGL's and condensate
168,574

 
46,479

 
—

 
215,053

Direct operating expenses
14,574

 
13,259

 
4,403

 
32,236

Selling, general and administrative expenses
 
 
 
 
 
 
19,079

Equity compensation expense
 
 
 
 
 
 
2,094

Depreciation, amortization and accretion expense
 
 
 
 
 
 
30,002

Total operating expenses
 
 
 
 
 
 
298,464

Gain (loss) on involuntary conversion of property, plant and equipment
 
 
 
 
 
 
343

Loss on impairment of property, plant and equipment
 
 
 
 
 
 
(18,155
)
Interest expense
 
 
 
 
 
 
(9,291
)
Income tax (expense) benefit
 
 
 
 
 
 
495

Income (loss) from discontinued operations, net of tax
 
 
 
 
 
 
(2,413
)
Net income (loss)
 
 
 
 
 
 
(33,406
)
Less: Net income (loss) attributable to noncontrolling interests
 
 
 
 
 
 
633

Net income (loss) attributable to the Partnership
 
 
 
 
 
 
$
(34,039
)
 
 
 
 
 
 
 
 
Segment gross margin (a)
$
36,985

 
$
32,408

 
$
5,428

 
$
74,821


 
December 31,
 
2015
 
2014
Segment assets:
 
 
 
Gathering and Processing
$
572,824

 
$
686,395

Transmission
133,870

 
132,767

Terminals
84,449

 
68,094

Other (c)
100,153

 
26,302

Total assets
$
891,296

 
$
913,558


(a)
Segment gross margin for our Gathering and Processing segment consists of revenue less purchases of natural gas, NGLs and condensate and COMA. Segment gross margin for our Transmission segment consists of revenue, less purchases of natural gas and COMA. Segment gross margin for our Terminals segment consists of revenue, less direct operating expenses. Gross margin consists of the sum of the segment gross margin amounts for each of these segments. As an indicator of our operating performance, gross margin should not be considered an alternative to, or more meaningful than, net income or cash flow from operations as determined in accordance with GAAP. Our gross margin may not be comparable to a similarly titled measure of another company because other entities may not calculate gross margin in the same manner.
(b)
Terminals segment amounts are for the period from April 15, 2013 to December 31, 2013.
(c)
Other assets not allocable to segments consist of investment in unconsolidated affiliate, corporate leasehold improvements, and other assets.

For a definition of gross margin and a reconciliation to its most directly comparable financial measure calculated and presented in accordance with GAAP and a discussion of how we use gross margin to evaluate our operating performance, please read Item 7. "Management's Discussion and Analysis, How We Evaluate Our Operations."

Percentage of revenue earned from major customers 
The following table summarizes those customers who accounted for more than 10% of the Partnership's consolidated revenue for the each of the last three years:

 
Years Ended December 31,
 
2015
 
2014
 
2013
Customer A
10
%
 
22
%
 
28
%
Customer B
—
%
 
—
%
 
13
%
Customer C
—
%
 
12
%
 
12
%
Customer D
—
%
 
10
%
 
10
%
Other
90
%
 
56
%
 
37
%
Total
100
%
 
100
%
 
100
%
The following table summarizes the percentage of revenue earned from those customers in each segment that exceed 10% of the Partnership's consolidated segment's revenue for the each of the periods presented below:

 
Years Ended December 31,
 
2015
 
2014
 
2013
Gathering and Processing:
 
 
 
 
 
Customer A
12
%
 
33
%
 
43
%
Customer B
—
%
 
12
%
 
19
%
Customer J
12
%
 
—
%
 
—
%
Other
76
%
 
55
%
 
38
%
Total
100
%
 
100
%
 
100
%
Transmission:
 
 
 
 
 
Customer C
—
%
 
43
%
 
39
%
Customer D
16
%
 
16
%
 
16
%
Customer K
19
%
 
—
%
 
—
%
Other
65
%
 
41
%
 
45
%
Total
100
%
 
100
%
 
100
%
Terminals:
 
 
 
 
 
Customer F
13
%
 
19
%
 
20
%
Customer B
13
%
 
20
%
 
17
%
Customer G
21
%
 
15
%
 
16
%
Customer H
—
%
 
11
%
 
13
%
Customer I
13
%
 
—
%
 
—
%
Other
40
%
 
35
%
 
34
%
Total
100
%
 
100
%
 
100
%
Quarterly Financial Data (Tables)
Schedule of Quarterly Financial Information [Table Text Block]
Summarized unaudited quarterly financial data for 2015 and 2014 are as follows (in thousands, except per unit amounts):
 
 
First
Quarter
 
Second
Quarter
 
Third
Quarter
 
Fourth
Quarter (b)
Year Ended December 31, 2015
 
 
 
 
 
 
 
Total revenues
$
64,609

 
$
67,509

 
$
55,641

 
$
48,599

Gross margin (a)
33,776

 
32,304

 
29,134

 
28,067

Operating income (loss)
3,434

 
1,867

 
(1,523
)
 
(123,475
)
Net income (loss) from continuing operations
835

 
(2,002
)
 
(4,574
)
 
(121,634
)
Income (loss) from discontinued operations, net of tax
5

 
(31
)
 
(53
)
 
(1
)
Net income (loss) attributable to noncontrolling interest
14

 
32

 
34

 
(55
)
Net income (loss) attributable to the Partnership
826

 
(2,065
)
 
(4,661
)
 
(121,580
)
General Partner's Interest in net income (loss)
10

 
(25
)
 
(60
)
 
(1,570
)
Limited Partners' Interest in net income (loss)
$
816

 
$
(2,040
)
 
$
(4,601
)
 
$
(120,010
)
 
 
 
 
 
 
 
 
Limited Partners' income (loss) per unit:
 
 
 
 
 
 
 
Income (loss) from continuing operations
$
(0.19
)
 
$
(0.35
)
 
$
(0.48
)
 
$
(4.16
)
Income (loss) from discontinued operations
—

 
—

 
—

 
—

Net income (loss)
$
(0.19
)
 
$
(0.35
)
 
$
(0.48
)
 
$
(4.16
)
Year Ended December 31, 2014
 
 
 
 
 
 
 
Total revenues
$
80,238

 
$
77,680

 
$
70,305

 
$
80,177

Gross margin (a)
23,081

 
22,167

 
21,332

 
36,227

Operating income (loss)
2,450

 
734

 
(290
)
 
(91,633
)
Net income (loss) from continuing operations
558

 
(1,095
)
 
(2,397
)
 
(94,261
)
Income (loss) from discontinued operations, net of tax
(50
)
 
(506
)
 
(26
)
 
(29
)
Net income (loss) attributable to noncontrolling interest
108

 
66

 
33

 
7

Net income (loss) attributable to the Partnership
400

 
(1,667
)
 
(2,456
)
 
(94,297
)
General Partner's Interest in net income (loss)
7

 
(22
)
 
(32
)
 
(1,232
)
Limited Partners' Interest in net income (loss)
$
393

 
$
(1,645
)
 
$
(2,424
)
 
$
(93,065
)
 
 
 
 
 
 
 
 
Limited Partners' income (loss) per unit:
 
 
 
 
 
 
 
Income (loss) from continuing operations
$
(0.31
)
 
$
(0.55
)
 
$
(0.58
)
 
$
(4.98
)
Income (loss) from discontinued operations
(0.01
)
 
(0.04
)
 
—

 
—

Net income (loss)
$
(0.32
)
 
$
(0.59
)
 
$
(0.58
)
 
$
(4.98
)
 
(a)
For a definition of gross margin and a reconciliation to its most directly comparable financial measure calculated and presented in accordance with GAAP and a discussion of how we use gross margin to evaluate our operating performance, please read Item 7. "Management's Discussion and Analysis, How We Evaluate Our Operations."
(b)
In the fourth quarter of 2015, we recognized a Loss on impairment of goodwill of $118.6 million. In the fourth quarter of 2014, we recognized a Loss on impairment of property, plant and equipment of $99.9 million.
Organization and Basis of Presentation (Details)
12 Months Ended 12 Months Ended
Dec. 31, 2015
billion_cubic_feet_per_day
mi
bbl
facility
gathering_system
pipeline
Dec. 31, 2015
Burns Point Plant [Member]
Dec. 31, 2015
Minimum [Member]
Dec. 31, 2015
Maximum [Member]
Dec. 31, 2015
MPOG [Member]
Aug. 11, 2014
MPOG [Member]
Dec. 31, 2015
Mesquite [Member]
Dec. 31, 2015
Delta House [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
 
 
 
 
 
 
 
 
General Partners' Capital Account, Percentage
95.00% 
 
 
 
 
 
 
 
Limited Partners' Capital Account, Percentage
5.00% 
 
 
 
 
 
 
 
Number of Gathering Systems
12 
 
 
 
 
 
 
 
Number of Processing Facilities
5 
 
 
 
 
 
 
 
Number of Fractionation Facilities
3 
 
 
 
 
 
 
 
Number of Marine Terminal Sites
3 
 
 
 
 
 
 
 
Number of Interstate Pipelines
3 
 
 
 
 
 
 
 
Number of Intrastate Pipelines
5 
 
 
 
 
 
 
 
Number of Oil Pipelines
1 
 
 
 
 
 
 
 
Ownership percentage
 
 
 
 
66.70% 
66.70% 
46.00% 
12.90% 
Acquired interest (percent)
 
50.00% 
 
 
 
 
 
 
Gathering pipeline (miles)
3,000 
 
 
 
 
 
 
 
Volume of Natural Gas, Operating
1 
 
 
 
 
 
 
 
Million barrels of storage capacity
1,800,000 
 
 
 
 
 
 
 
Useful life
 
 
10 years 0 months 0 days 
30 years 
 
 
 
 
Noncontrolling interest, ownership percentage by noncontrolling owners
7.80% 
 
 
 
 
 
 
 
Acquisitions (Consideration Transferred) (Details) (Costar Midstream, L.L.C. [Member], USD $)
0 Months Ended 12 Months Ended
Oct. 14, 2014
Dec. 31, 2015
Dec. 31, 2014
Costar Midstream, L.L.C. [Member]
 
 
 
Business Acquisition [Line Items]
 
 
 
Cash
$ 258,001,000 
 
 
Limited partner common units
147,296,000 
0 
147,296,000 
Total fair value of consideration
$ 405,297,000 
 
 
Acquisitions Fair Value of Identifiable Assets and Consideration Transferred (Details) (USD $)
0 Months Ended 0 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Oct. 14, 2014
Costar Midstream, L.L.C. [Member]
Oct. 14, 2014
Costar Midstream, L.L.C. [Member]
Jan. 31, 2014
Lavaca [Member]
Jan. 31, 2014
Lavaca [Member]
Apr. 15, 2013
High Point [Member]
Jan. 31, 2014
Pipelines [Member]
Lavaca [Member]
Business Acquisition [Line Items]
 
 
 
 
 
 
 
 
 
Working capital
 
 
 
 
$ 8,152,000 
 
 
 
 
Processing plants
 
 
 
 
48,357,000 
 
 
 
 
Pipelines
 
 
 
 
128,799,000 
 
 
 
 
Land
 
 
 
 
1,244,000 
 
2,000 
 
 
Buildings
 
 
 
 
682,000 
 
 
 
 
Equipment
 
 
 
 
9,827,000 
 
753,000 
 
 
Construction in progress
 
 
 
 
16,146,000 
 
 
 
 
Total property, plant and equipment
 
 
 
 
205,055,000 
 
59,492,000 
 
58,737,000 
Investment in unconsolidated affiliate
 
 
 
 
11,884,000 
 
 
 
 
Customer relationships
 
 
 
 
53,400,000 
 
 
 
 
Dedicated acreage
 
 
 
 
32,000,000 
 
 
 
 
Noncontrolling interest
 
 
 
 
(219,000)
 
 
 
 
Goodwill
16,300,000 
142,236,000 
 
 
95,025,000 
 
23,567,000 
 
 
Intangible assets
 
 
 
 
 
 
21,350,000 
 
 
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest
 
 
 
 
405,297,000 
 
 
 
 
Total identifiable net assets
 
 
 
 
 
 
 
61,900,000 
 
Property, plant and equipment
648,013,000 
582,182,000 
 
 
 
 
 
 
 
Asset retirement cost
35,371,000 
34,645,000 
34,636,000 
 
 
 
 
 
 
Accounts payable
4,667,000 
20,326,000 
 
 
 
 
 
 
 
Accrued gas purchases
7,281,000 
14,326,000 
 
 
 
 
 
 
 
Asset retirement obligations
6,822,000 
0 
 
 
 
 
 
 
 
Cash
 
 
 
$ 258,001,000 
 
$ 104,409,000 
 
 
 
Acquisitions (Pro Forma Information) (Details) (Costar Midstream, L.L.C. [Member], USD $)
In Thousands, except Per Share data, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Costar Midstream, L.L.C. [Member]
 
 
Business Acquisition [Line Items]
 
 
Revenue
$ 435,133 
$ 448,748 
Net loss
$ (101,237)
$ (30,672)
Limited partners' net loss per unit
$ (6.15)
$ (3.82)
Acquisitions Narrative (Details) (USD $)
0 Months Ended 3 Months Ended 12 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 3 Months Ended 6 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 1 Months Ended 12 Months Ended 12 Months Ended 6 Months Ended 0 Months Ended 3 Months Ended 12 Months Ended 12 Months Ended 0 Months Ended 3 Months Ended 12 Months Ended 3 Months Ended 0 Months Ended 9 Months Ended 0 Months Ended 0 Months Ended 3 Months Ended 12 Months Ended 0 Months Ended
Oct. 8, 2015
Sep. 10, 2015
Jan. 29, 2014
Dec. 31, 2015
bbl
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Jun. 30, 2013
Dec. 31, 2015
mi
bbl
Dec. 31, 2014
Dec. 31, 2013
Oct. 8, 2015
Sep. 15, 2015
Sep. 10, 2015
Aug. 20, 2014
Jan. 29, 2014
Dec. 11, 2013
Apr. 15, 2013
Dec. 31, 2015
Series B
Dec. 31, 2014
Series B
Dec. 31, 2013
Series B
Jan. 31, 2014
Series B
Oct. 14, 2014
Costar Midstream, L.L.C. [Member]
Dec. 31, 2015
Costar Midstream, L.L.C. [Member]
Dec. 31, 2014
Costar Midstream, L.L.C. [Member]
Oct. 14, 2014
Costar Midstream, L.L.C. [Member]
Jan. 31, 2014
Lavaca [Member]
mi
Dec. 31, 2015
Lavaca [Member]
Dec. 31, 2014
Lavaca [Member]
Sep. 30, 2013
High Point [Member]
Jun. 30, 2015
High Point [Member]
mi
Apr. 15, 2013
High Point [Member]
Mar. 31, 2014
Williams [Member]
Dec. 31, 2015
Minimum [Member]
Oct. 14, 2014
Minimum [Member]
Costar Midstream, L.L.C. [Member]
Dec. 31, 2015
Maximum [Member]
Oct. 14, 2014
Maximum [Member]
Costar Midstream, L.L.C. [Member]
Dec. 31, 2015
General Partner [Member]
Dec. 31, 2014
General Partner [Member]
Dec. 31, 2013
General Partner [Member]
Dec. 31, 2015
Blackwater [Member]
Apr. 15, 2013
Total Partners Capital
Dec. 31, 2015
Total Partners Capital
Dec. 31, 2014
Total Partners Capital
Dec. 31, 2013
Total Partners Capital
Dec. 31, 2015
Total Partners Capital
Series B
Dec. 31, 2015
Series B
Jan. 31, 2014
Series B
Dec. 31, 2015
Series B
Dec. 31, 2014
Series B
Sep. 18, 2015
Pinto Offshore Holdings LLC [Member]
Sep. 18, 2015
Delta House FPS LLC [Member]
Sep. 18, 2015
Delta House Oil and Gas Lateral LLC [Member]
Sep. 18, 2015
Delta House [Member]
Dec. 31, 2015
Delta House [Member]
Dec. 31, 2014
Delta House [Member]
Aug. 14, 2014
MPOG [Member]
Dec. 31, 2015
MPOG [Member]
Dec. 31, 2014
MPOG [Member]
Aug. 11, 2014
MPOG [Member]
Dec. 31, 2015
Terminals [Member]
Dec. 31, 2014
Terminals [Member]
Dec. 31, 2013
Terminals [Member]
Dec. 17, 2013
Terminals [Member]
bbl
Jun. 30, 2015
ArcLight [Member]
High Point [Member]
Gas_Receipt_Point
Dec. 17, 2013
Blackwater [Member]
Mar. 31, 2014
Blackwater [Member]
Dec. 31, 2013
Blackwater [Member]
Dec. 17, 2013
Blackwater [Member]
Apr. 15, 2013
Blackwater [Member]
Dec. 31, 2013
Blackwater [Member]
General Partner [Member]
Apr. 15, 2013
Series A
Dec. 31, 2015
Series A
Dec. 31, 2015
Series A
Dec. 31, 2014
Series A
Apr. 15, 2013
Issuance of Preferred Units [Member]
High Point [Member]
Series A
Apr. 15, 2013
Revolving Credit Facility [Member]
Fourth Amendment [Member]
Series A
Apr. 15, 2013
AIM Midstream Holdings [Member]
High Point [Member]
Partnership Interest [Member]
Sep. 30, 2015
Salisbury [Member]
Sep. 14, 2015
Salisbury [Member]
Jun. 1, 2015
Eloi Bay [Member]
Jun. 1, 2015
Eloi Bay [Member]
Mar. 31, 2015
Madison [Member]
Mar. 31, 2014
Madison [Member]
Dec. 31, 2013
Madison [Member]
Dec. 31, 2015
MPOG [Member]
Dec. 31, 2014
MPOG [Member]
Feb. 12, 2016
Subsequent Event [Member]
Interest Rate Swap [Member]
Feb. 12, 2016
Subsequent Event [Member]
Interest Rate Swap [Member]
Business Acquisition [Line Items]
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Property, plant and equipment
 
 
 
$ 648,013,000 
 
 
 
$ 582,182,000 
 
 
 
 
$ 648,013,000 
$ 582,182,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 900,000 
 
$ 3,000,000 
 
 
 
 
 
 
 
Gain (Loss) on Disposition of Property Plant Equipment
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3,000,000 
 
 
 
 
 
 
 
 
Loss on sale of assets
 
 
 
 
 
 
 
 
 
 
 
 
(150,000)
(87,000)
(75,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
100,000 
 
 
 
 
 
 
 
 
 
 
Proceeds from sale of property, plant, and equipment
 
 
 
 
 
 
 
 
 
 
 
 
4,813,000 
6,323,000 
500,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6,100,000 
 
 
 
 
 
 
Noncontrolling interest, ownership percentage by noncontrolling owners
 
 
 
7.80% 
 
 
 
 
 
 
 
 
7.80% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Acquired interest (percent)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
100.00% 
 
 
 
 
 
100.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Cash
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
258,001,000 
 
 
 
104,409,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Equity interests issued (in units)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6,900,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Limited partner common units
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
147,296,000 
0 
147,296,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3,100,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Total identifiable net assets
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
61,900,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
22,700,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Partners' Capital Account, Distributions to Existing Interest
 
 
 
 
 
 
 
 
 
 
 
 
0 
0 
15,612,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
(312,000)
 
15,600,000 
 
 
(15,612,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Discount rate
 
 
 
 
 
 
 
9.50% 
 
 
 
 
10.00% 
 
10.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
10.50% 
 
 
 
 
 
 
 
11.00% 
 
16.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
18.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Working capital, accounts receivable
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
11,200,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Acquisition Working Capital Adjustment
 
 
 
 
 
 
 
 
 
 
 
 
7,400,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
EscrowedUnitsReturnedtoPartnership
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1,034,483 
Payments for Previous Acquisition
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
300,000 
 
Revenues
 
 
 
48,599,000 
55,641,000 
67,509,000 
64,609,000 
80,177,000 
70,305,000 
77,680,000 
80,238,000 
 
236,358,000 
308,400,000 
294,079,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
19,900,000 
 
 
 
16,800,000 
30,400,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
17,755,000 
15,504,000 
9,800,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Net income (loss)
 
 
 
(121,580,000)
(4,661,000)
(2,065,000)
826,000 
(94,297,000)
(2,456,000)
(1,667,000)
400,000 
 
(127,480,000)
(98,020,000)
(34,039,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7,200,000 
 
 
 
 
 
 
 
 
 
 
 
 
(127,480,000)
(98,020,000)
(34,039,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Operating income (loss)
 
 
 
(123,475,000)
(1,523,000)
1,867,000 
3,434,000 
(91,633,000)
(290,000)
734,000 
2,450,000 
 
(119,697,000)
(88,739,000)
(22,197,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
300,000 
 
 
 
7,600,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
800,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Transaction costs
 
 
 
 
 
 
 
100,000 
 
 
 
 
 
100,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
500,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Length Of Pipeline
 
 
 
 
 
 
 
 
 
 
 
 
3,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
120 
 
 
 
700 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Issuance of common units, net of offering costs
1,700,000 
81,000,000 
86,900,000 
 
 
 
 
 
 
 
 
 
 
119,300,000 
54,900,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
0 
 
 
 
 
 
351,551,000 
 
 
0 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Issuance of Series B Units
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1,373,000 
 
30,000,000 
1,373,000 
32,220,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Limited partners, units issued
 
 
 
30,427,000 
 
 
 
22,670,000 
 
 
 
 
30,427,000 
22,670,000 
7,414,000 
151,937 
7,500,000 
7,500,000 
4,622,352 
3,400,000 
2,568,712 
 
 
 
 
1,168,225 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Useful life
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
25 years 
 
 
 
 
 
 
10 years 0 months 0 days 
 
30 years 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Loss on impairment of goodwill
 
 
 
 
 
 
 
 
 
 
 
 
118,592,000 
0 
0 
 
 
 
 
 
 
 
 
 
 
 
 
95,000,000 
 
 
 
23,600,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Finite-lived intangible assets, amortization expense, next twelve months
 
 
 
4,300,000 
 
 
 
 
 
 
 
 
4,300,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Ownership percentage
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
26.30% 
49.00% 
49.00% 
 
12.90% 
 
 
66.70% 
 
66.70% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Payments to acquire equity method investments
 
 
 
 
 
 
 
 
 
 
 
 
71,597,000 
12,000,000 
0 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
162,000,000 
 
 
12,000,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Earnings in unconsolidated affiliates
 
 
 
 
 
 
 
 
 
 
 
 
8,201,000 
348,000 
0 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7,470,000 
0 
 
731,000 
348,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
700,000 
300,000 
 
 
Distributions from unconsolidated affiliates
 
 
 
 
 
 
 
 
 
 
 
 
8,201,000 
348,000 
0 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
16,600,000 
 
 
3,900,000 
2,000,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Proceeds from equity method investement, return of capital
 
 
 
 
 
 
 
 
 
 
 
 
12,367,000 
1,632,000 
0 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Total Consideration
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6,500,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Million barrels of storage capacity
 
 
 
1,800,000 
 
 
 
 
 
 
 
 
1,800,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1,300,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Total fair value of consideration
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
405,297,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
63,900,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Distributions
 
 
 
 
 
 
 
 
 
 
 
 
53,386,000 
28,009,000 
16,120,000 
 
 
 
 
 
 
 
1,373,000 
2,220,000 
0 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7,023,000 
2,913,000 
623,000 
(500,000)
 
71,737,000 
42,063,000 
22,251,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
27,700,000 
27,650,000 
 
 
30,702,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Units issued in business acquisition
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
125,500 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Number of natural gas collection receipt points
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
75 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Total Consideration for Issuance of Preferred Units
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
15,000,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Contributed capital
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5,142,857 
 
 
 
 
 
 
 
 
 
 
 
 
 
Transaction expenses
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2,500,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
Payments on long-term debt
 
 
 
 
 
 
 
 
 
 
 
 
189,150,000 
250,870,000 
131,571,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
12,500,000 
 
 
 
 
 
 
 
 
 
 
 
 
Partnership cancellation of subordinated units (percent)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
90.00% 
 
 
 
 
 
 
 
 
 
 
 
Distribution made to member or limited partner, distributions paid, conversion price per unit
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 17.50 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Series A convertible preferred units
 
 
 
169,712,000 
 
 
 
107,965,000 
 
 
 
 
169,712,000 
107,965,000 
 
 
 
 
 
 
 
90,000,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Distribution growth rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Fair value input, option value
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
0.07 
 
9.68 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Loss on impairment of property, plant and equipment
 
 
 
 
 
 
 
99,900,000 
 
 
 
15,200,000 
0 
99,892,000 
18,155,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3,000,000 
 
 
 
 
 
Property plant and equipment gross
 
 
 
793,976,000 
 
 
 
698,017,000 
 
 
 
 
793,976,000 
698,017,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6,100,000 
 
 
 
 
Payments to Acquire Interest in Subsidiaries and Affiliates
 
 
 
 
 
 
 
 
 
 
 
 
65,703,000 
23,884,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
65,703,000 
0 
 
0 
12,000,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Partners Capital Account Distributions, Delta House
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ (96,297,000)
 
 
$ 27,700,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Discontinued Operations (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
 
 
 
 
 
 
 
 
 
 
 
Revenue
 
 
 
 
 
 
 
 
$ 74 
$ 474 
$ 2,084 
Expense
 
 
 
 
 
 
 
 
(196)
(658)
(2,361)
Impairment
 
 
 
 
 
 
 
 
0 
(673)
(2,400)
Loss on sale of assets
 
 
 
 
 
 
 
 
(150)
(87)
(75)
Income tax benefit
 
 
 
 
 
 
 
 
192 
333 
339 
Income (loss) from discontinued operations, net of tax
(1)
(53)
(31)
5 
(29)
(26)
(506)
(50)
(80)
(611)
(2,413)
Limited Partners' net income (loss) from discontinued operations per unit (basic and diluted)
$ 0.00 
$ 0.00 
$ 0.00 
$ 0.00 
$ 0.00 
$ 0.00 
$ (0.04)
$ (0.01)
$ 0.00 
$ (0.04)
$ (0.27)
Loss on impairment of noncurrent assets held for sale
 
 
 
 
 
 
 
 
0 
673 
2,400 
Discount rate
 
 
 
 
9.50% 
 
 
 
10.00% 
 
10.00% 
Gathering And Processing [Member]
 
 
 
 
 
 
 
 
 
 
 
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
 
 
 
 
 
 
 
 
 
 
 
Loss on impairment of noncurrent assets held for sale
 
 
 
 
 
 
 
 
 
 
1,800 
Terminals [Member]
 
 
 
 
 
 
 
 
 
 
 
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
 
 
 
 
 
 
 
 
 
 
 
Loss on impairment of noncurrent assets held for sale
 
 
 
 
 
 
 
 
 
 
$ 600 
Concentration of Credit Risk and Trade Accounts Receivable (Details)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Revenue, Major Customer
 
 
 
Entity-wide revenue by major customer, percentage
100.00% 
100.00% 
100.00% 
Customer A [Member]
 
 
 
Revenue, Major Customer
 
 
 
Entity-wide revenue by major customer, percentage
10.00% 
22.00% 
28.00% 
Customer B [Member]
 
 
 
Revenue, Major Customer
 
 
 
Entity-wide revenue by major customer, percentage
0.00% 
0.00% 
13.00% 
Customer C [Member]
 
 
 
Revenue, Major Customer
 
 
 
Entity-wide revenue by major customer, percentage
0.00% 
12.00% 
12.00% 
Customer D [Member]
 
 
 
Revenue, Major Customer
 
 
 
Entity-wide revenue by major customer, percentage
0.00% 
10.00% 
10.00% 
Customer Other [Member]
 
 
 
Revenue, Major Customer
 
 
 
Entity-wide revenue by major customer, percentage
90.00% 
56.00% 
37.00% 
Other Current Assets (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2015
Dec. 31, 2014
Other Current Assets [Abstract]
 
 
Prepaid insurance—current portion
$ 3,948 
$ 4,162 
Restricted cash
0 
6,475 
Other prepaid amounts
2,866 
758 
Other current assets
3,280 
4,159 
Other current assets
$ 10,094 
$ 15,554 
Derivatives (Fair Value of Commodity Derivatives) (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2015
Dec. 31, 2014
Derivative [Line Items]
 
 
Derivative Asset, Fair Value, Net
$ 365 
$ 688 
Derivative Liability, Fair Value, Net
0 
(215)
Commodity derivatives [Member]
 
 
Derivative [Line Items]
 
 
Derivative asset, gross derivative asset
365 
688 
Derivative asset, gross derivative liabilities
0 
0 
Derivative liability, gross derivative assets
0 
0 
Derivative liability, gross derivative liabilities
0 
(215)
Commodity derivatives [Member] |
Risk Management Assets [Member]
 
 
Derivative [Line Items]
 
 
Derivative asset, gross derivative asset
365 
688 
Derivative asset, gross derivative liabilities
0 
0 
Derivative Asset, Fair Value, Net
365 
688 
Commodity derivatives [Member] |
Risk Management Assets - Long Term [Member]
 
 
Derivative [Line Items]
 
 
Derivative asset, gross derivative asset
0 
0 
Derivative asset, gross derivative liabilities
0 
0 
Derivative Asset, Fair Value, Net
0 
0 
Commodity derivatives [Member] |
Risk Management Liabilities [Member]
 
 
Derivative [Line Items]
 
 
Derivative liability, gross derivative assets
0 
0 
Derivative liability, gross derivative liabilities
0 
(215)
Derivative Liability, Fair Value, Net
0 
(215)
Commodity derivatives [Member] |
Risk Management Liabilities - Long Term [Member]
 
 
Derivative [Line Items]
 
 
Derivative liability, gross derivative assets
0 
0 
Derivative liability, gross derivative liabilities
0 
0 
Derivative Liability, Fair Value, Net
$ 0 
$ 0 
Derivatives (Realized and Unrealized Gains (Losses)) (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Derivatives, Fair Value [Line Items]
 
 
 
Gain (loss) on commodity derivatives, net
$ 1,324 
$ 1,091 
$ 28 
Commodity derivatives [Member]
 
 
 
Derivatives, Fair Value [Line Items]
 
 
 
Gain (loss) on commodity derivatives, net
457 
(733)
200 
Gain (loss) on derivatives, unrealized
(71)
595 
(1,495)
Commodity derivatives [Member] |
Gain (Loss) on Derivative Instruments [Member]
 
 
 
Derivatives, Fair Value [Line Items]
 
 
 
Gain (loss) on commodity derivatives, net
1,610 
735 
1,069 
Gain (loss) on derivatives, unrealized
(286)
356 
(1,041)
Commodity derivatives [Member] |
Interest Expense [Member]
 
 
 
Derivatives, Fair Value [Line Items]
 
 
 
Gain (loss) on commodity derivatives, net
(240)
(433)
(207)
Gain (loss) on derivatives, unrealized
215 
239 
(454)
Commodity derivatives [Member] |
Other Income [Member]
 
 
 
Derivatives, Fair Value [Line Items]
 
 
 
Gain (loss) on commodity derivatives, net
(913)
(1,035)
(662)
Gain (loss) on derivatives, unrealized
$ 0 
$ 0 
$ 0 
Derivatives (Details Textual) (USD $)
12 Months Ended 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Aug. 1, 2015
Interest Rate Swap [Member]
Dec. 31, 2015
Weather Contract [Member]
Dec. 31, 2014
Weather Contract [Member]
Mar. 2, 2016
Subsequent Event [Member]
Interest Rate Swap [Member]
Derivative [Line Items]
 
 
 
 
 
 
 
Notional amount of interest rate derivatives
 
 
 
$ 100,000,000 
 
 
$ 200,000,000 
Derivative instruments not designated as hedging instruments, potential cash proceeds from Contract
 
 
 
 
10,000,000 
 
 
Derivative instruments not designated as hedging instruments, asset, at fair value
 
 
 
 
0 
 
 
Payments of derivative issuance costs
 
 
 
 
900,000 
1,000,000 
 
Term of Contract
 
 
 
 
1 year 0 months 0 days 
 
 
Amortization of weather derivative premium
$ 912,000 
$ 1,035,000 
$ 662,000 
 
$ 400,000 
$ 400,000 
 
Fair Value Measurement (Fair Value of Financial Instruments) (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2015
Dec. 31, 2014
Commodity Contract [Member]
 
 
Quantitative Information about Level 3 Fair Value Measurements
 
 
Estimated Fair Value
$ 0 
$ 286 
Interest Rate Swap [Member]
 
 
Quantitative Information about Level 3 Fair Value Measurements
 
 
Estimated Fair Value
0 
(215)
Estimate of Fair Value Measurement [Member] |
Commodity Contract [Member]
 
 
Quantitative Information about Level 3 Fair Value Measurements
 
 
Estimated Fair Value
0 
286 
Estimate of Fair Value Measurement [Member] |
Commodity Contract [Member] |
Level 1 [Member]
 
 
Quantitative Information about Level 3 Fair Value Measurements
 
 
Estimated Fair Value
0 
0 
Estimate of Fair Value Measurement [Member] |
Commodity Contract [Member] |
Level 2 [Member]
 
 
Quantitative Information about Level 3 Fair Value Measurements
 
 
Estimated Fair Value
0 
286 
Estimate of Fair Value Measurement [Member] |
Commodity Contract [Member] |
Level 3 [Member]
 
 
Quantitative Information about Level 3 Fair Value Measurements
 
 
Estimated Fair Value
0 
0 
Estimate of Fair Value Measurement [Member] |
Interest Rate Swap [Member]
 
 
Quantitative Information about Level 3 Fair Value Measurements
 
 
Estimated Fair Value
0 
(215)
Estimate of Fair Value Measurement [Member] |
Interest Rate Swap [Member] |
Level 1 [Member]
 
 
Quantitative Information about Level 3 Fair Value Measurements
 
 
Estimated Fair Value
0 
0 
Estimate of Fair Value Measurement [Member] |
Interest Rate Swap [Member] |
Level 2 [Member]
 
 
Quantitative Information about Level 3 Fair Value Measurements
 
 
Estimated Fair Value
0 
(215)
Estimate of Fair Value Measurement [Member] |
Interest Rate Swap [Member] |
Level 3 [Member]
 
 
Quantitative Information about Level 3 Fair Value Measurements
 
 
Estimated Fair Value
$ 0 
$ 0 
Fair Value Measurement (Details Textual) (USD $)
12 Months Ended
Dec. 31, 2015
Fair Value Disclosures [Abstract]
 
Transfers out of Level 3
$ 0 
Property, Plant and Equipment, Net (Details) (USD $)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Property, Plant and Equipment [Line Items]
 
 
 
Loss on impairment of noncurrent assets held for sale
$ 0 
$ 673,000 
$ 2,400,000 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Property plant and equipment gross
793,976,000 
698,017,000 
 
Accumulated depreciation
(145,963,000)
(115,835,000)
 
Property, plant and equipment, net
648,013,000 
582,182,000 
 
Interest Costs Capitalized
1,900,000 
800,000 
200,000 
Depreciation
31,900,000 
23,900,000 
25,900,000 
Land [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Property plant and equipment gross
5,282,000 
5,282,000 
 
Construction in progress [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Property plant and equipment gross
46,045,000 
77,550,000 
 
Buildings and improvements [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Property plant and equipment gross
9,864,000 
6,855,000 
 
Processing and treating plants [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Property plant and equipment gross
97,784,000 
80,837,000 
 
Pipelines [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Property plant and equipment gross
554,400,000 
476,997,000 
 
Equipment [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Property plant and equipment gross
22,207,000 
12,345,000 
 
Tanks, truck rack and piping [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Property plant and equipment gross
58,394,000 
38,151,000 
 
Minimum [Member] |
Buildings and improvements [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Useful Life (in years)
4 years 
 
 
Minimum [Member] |
Processing and treating plants [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Useful Life (in years)
8 years 
 
 
Minimum [Member] |
Pipelines [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Useful Life (in years)
3 years 
 
 
Minimum [Member] |
Equipment [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Useful Life (in years)
5 years 
 
 
Minimum [Member] |
Tanks, truck rack and piping [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Useful Life (in years)
20 years 
 
 
Maximum [Member] |
Buildings and improvements [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Useful Life (in years)
40 years 
 
 
Maximum [Member] |
Processing and treating plants [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Useful Life (in years)
40 years 
 
 
Maximum [Member] |
Pipelines [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Useful Life (in years)
40 years 
 
 
Maximum [Member] |
Equipment [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Useful Life (in years)
20 years 
 
 
Maximum [Member] |
Tanks, truck rack and piping [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Useful Life (in years)
40 years 
 
 
Ala Tenn System [Member]
 
 
 
Property, Plant and Equipment, Net [Abstract]
 
 
 
Property plant and equipment gross
111,900,000 
101,900,000 
 
Gathering And Processing [Member]
 
 
 
Property, Plant and Equipment [Line Items]
 
 
 
Loss on impairment of noncurrent assets held for sale
 
 
$ 1,800,000 
Property, Plant and Equipment, Net (Asset Impairments and Insurance Proceeds) (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2014
Jun. 30, 2013
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Property, Plant and Equipment [Line Items]
 
 
 
 
 
Loss on impairment of property, plant and equipment
$ 99,900 
$ 15,200 
$ 0 
$ 99,892 
$ 18,155 
Discount rate
9.50% 
 
10.00% 
 
10.00% 
Impairment of long lived assets
 
 
0 
673 
2,400 
Insurance proceeds from involuntary conversion of property, plant and equipment
 
 
0 
0 
482 
Gain (loss) on involuntary conversion of property, plant and equipment
 
 
0 
0 
343 
Fair Value, Inputs, Level 3 [Member] |
Income Approach Valuation Technique [Member]
 
 
 
 
 
Property, Plant and Equipment [Line Items]
 
 
 
 
 
Throughput volume decline rate
 
 
 
 
2.50% 
Gathering And Processing [Member]
 
 
 
 
 
Property, Plant and Equipment [Line Items]
 
 
 
 
 
Impairment of long lived assets
 
 
 
 
$ 1,800 
Goodwill and Intangible assets (Details) (USD $)
12 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2014
Gathering And Processing [Member]
Dec. 31, 2014
Terminals [Member]
Dec. 31, 2015
Minimum [Member]
Dec. 31, 2015
Maximum [Member]
Jan. 31, 2014
Lavaca [Member]
Dec. 31, 2015
Lavaca [Member]
Jan. 31, 2014
Lavaca [Member]
Dec. 31, 2015
Costar Midstream, L.L.C. [Member]
Oct. 14, 2014
Costar Midstream, L.L.C. [Member]
Goodwill [Line Items]
 
 
 
 
 
 
 
 
 
 
 
 
Goodwill, Impairment Loss
$ (118,592,000)
$ 0 
$ 0 
 
 
 
 
 
$ (23,600,000)
 
$ (95,000,000)
 
Goodwill
16,300,000 
142,236,000 
 
125,900,000 
16,300,000 
 
 
 
 
23,567,000 
 
95,025,000 
Useful life
 
 
 
 
 
10 years 0 months 0 days 
30 years 
25 years 
 
 
 
 
Amortization of Intangible Assets
5,300,000 
4,100,000 
3,700,000 
 
 
 
 
 
 
 
 
 
Finite-lived intangible assets, amortization expense, next twelve months
$ 4,300,000 
 
 
 
 
 
 
 
 
 
 
 
Goodwill and Intangible assets Schedule of intangible assets (Details) (USD $)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
 
 
 
Amortization of Intangible Assets
$ 5,300,000 
$ 4,100,000 
$ 3,700,000 
Goodwill
16,300,000 
142,236,000 
 
Gross carrying amount
118,851,000 
118,851,000 
 
Accumulated amortization
(17,886,000)
(12,545,000)
 
Net carrying amount
100,965,000 
106,306,000 
 
Customer Contracts [Member]
 
 
 
Finite-Lived Intangible Assets [Line Items]
 
 
 
Gross carrying amount
12,101,000 
12,101,000 
 
Accumulated amortization
(12,101,000)
(11,110,000)
 
Net carrying amount
0 
991,000 
 
Customer Relationships [Member]
 
 
 
Finite-Lived Intangible Assets [Line Items]
 
 
 
Gross carrying amount
53,400,000 
53,400,000 
 
Accumulated amortization
(3,124,000)
(553,000)
 
Net carrying amount
50,276,000 
52,847,000 
 
Dedicated Acreage [Member]
 
 
 
Finite-Lived Intangible Assets [Line Items]
 
 
 
Gross carrying amount
53,350,000 
53,350,000 
 
Accumulated amortization
(2,661,000)
(882,000)
 
Net carrying amount
50,689,000 
52,468,000 
 
Terminals [Member]
 
 
 
Finite-Lived Intangible Assets [Line Items]
 
 
 
Goodwill
 
16,300,000 
 
Gathering And Processing [Member]
 
 
 
Finite-Lived Intangible Assets [Line Items]
 
 
 
Goodwill
 
$ 125,900,000 
 
Investment in unconsolidated affiliates (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended 12 Months Ended 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2015
MPOG [Member]
Dec. 31, 2014
MPOG [Member]
Aug. 11, 2014
MPOG [Member]
Dec. 31, 2013
MPOG [Member]
Dec. 31, 2015
Mesquite [Member]
Dec. 31, 2014
Mesquite [Member]
Dec. 31, 2013
Mesquite [Member]
Dec. 31, 2015
Delta House [Member]
Dec. 31, 2014
Delta House [Member]
Dec. 31, 2013
Delta House [Member]
Schedule of Equity Method Investments [Line Items]
 
 
 
 
 
 
 
 
 
 
 
 
 
Equity Method Investment, Summarized Financial Information, Revenue
$ 37,724 
$ 3,847 
$ 0 
 
 
 
 
 
 
 
 
 
 
Equity Method Investment, Summarized Financial Information, Current Assets
2,086 
2,196 
 
 
 
 
 
 
 
 
 
 
 
Ownership percentage
 
 
 
66.70% 
 
66.70% 
 
46.00% 
 
 
12.90% 
 
 
Equity Method Investments
82,301 
22,252 
0 
7,179 
10,368 
 
0 
18,597 
11,884 
0 
56,525 
0 
0 
Payments to Acquire Interest in Subsidiaries and Affiliates
65,703 
23,884 
 
0 
12,000 
 
 
0 
11,884 
 
65,703 
0 
 
Earnings in unconsolidated affiliates
8,201 
348 
0 
731 
348 
 
 
0 
0 
 
7,470 
0 
 
Cash Dividends Paid to Parent Company by Unconsolidated Subsidiaries
(20,568)
(1,980)
 
(3,920)
(1,980)
 
 
0 
0 
 
(16,648)
0 
 
Cash Call For Expansion Projects
6,713 
 
 
0 
 
 
 
6,713 
 
 
0 
 
 
Equity Method Investment, Summarized Financial Information, Noncurrent Assets
288,617 
62,635 
 
 
 
 
 
 
 
 
 
 
 
Equity Method Investment, Summarized Financial Information, Current Liabilities
366 
398 
 
 
 
 
 
 
 
 
 
 
 
Equity Method Investment, Summarized Financial Information, Noncurrent Liabilities
23,617 
22,307 
 
 
 
 
 
 
 
 
 
 
 
Equity Method Investment Summarized Financial Information Operating Expenses
3,375 
1,722 
0 
 
 
 
 
 
 
 
 
 
 
Equity Method Investment, Summarized Financial Information, Net Income (Loss)
$ 29,437 
$ 510 
$ 0 
 
 
 
 
 
 
 
 
 
 
Accrued Expenses and Other Current Liabilities (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2015
Dec. 31, 2014
Payables and Accruals [Abstract]
 
 
Current portion of asset retirement obligation
$ 6,822 
$ 0 
Accrued capital expenditures
3,984 
17,134 
Accrued expenses
3,178 
4,560 
Due to related parties
3,894 
659 
Gas imbalances payable
413 
1,055 
Other
6,744 
2,392 
Accrued expenses and other current liabilities
$ 25,035 
$ 25,800 
Asset Retirement Obligation (Details) (USD $)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Asset Retirement Obligation Disclosure [Abstract]
 
 
Balance at beginning of period
$ 34,645,000 
$ 34,636,000 
Additions
0 
248,000 
Expenditures
(91,000)
(1,030,000)
Accretion expense
817,000 
791,000 
Balance at end of period
35,371,000 
34,645,000 
Current portion of asset retirement obligation
6,822,000 
0 
Asset Retirement Obligations, Noncurrent
28,549,000 
34,645,000 
Restricted Cash and Cash Equivalents
$ 5,000,000 
 
Debt Obligations (Outstanding Borrowings) (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2015
Dec. 31, 2014
Debt Disclosure [Abstract]
 
 
Revolving credit facility
$ 525,100 
$ 372,950 
Other debt
2,338 
2,908 
Total debt
527,438 
375,858 
Less: current portion
2,338 
2,908 
Long-term debt
$ 525,100 
$ 372,950 
Debt Obligations (Textual) (Details) (USD $)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Debt Instrument [Line Items]
 
 
 
Line of Credit Facility, Current Borrowing Capacity
$ 750,000,000 
 
 
Line of Credit Facility, Maximum Borrowing Capacity Upon Increase
900,000,000 
 
 
Unused capacity, commitment fee percentage
0.50% 
 
 
Ratio of indebtedness to net capital
4.56 
 
 
Interest coverage ratio
8.56 
 
 
Debt, weighted average interest rate
3.67% 
3.80% 
4.53% 
Letters of credit outstanding amount
1,800,000 
1,600,000 
 
Revolving credit facility
525,100,000 
372,950,000 
 
Proceeds from (payments for) other financing activities
3,000,000 
 
 
Periodic payment
$ 300,000 
 
 
Minimum [Member]
 
 
 
Debt Instrument [Line Items]
 
 
 
Interest coverage ratio
2.50 
 
 
Maximum [Member]
 
 
 
Debt Instrument [Line Items]
 
 
 
Ratio of indebtedness to net capital
4.75 
 
 
Ratio of indebtedness to net capital, after allowed acquisition
5.25 
 
 
Federal Funds [Member]
 
 
 
Debt Instrument [Line Items]
 
 
 
Facility fee (percent)
0.50% 
 
 
Eurodollar [Member]
 
 
 
Debt Instrument [Line Items]
 
 
 
Facility fee (percent)
1.00% 
 
 
Insurance Premium Financing [Member]
 
 
 
Debt Instrument [Line Items]
 
 
 
Facility fee (percent)
3.95% 
 
 
Fiscal Quarter Ending December 31, 2014 [Member] |
Fourth Amendment [Member] |
Base Rate [Member] |
Minimum [Member]
 
 
 
Debt Instrument [Line Items]
 
 
 
Basis spread on variable rate
2.00% 
 
 
Fiscal Quarter Ending December 31, 2014 [Member] |
Fourth Amendment [Member] |
Base Rate [Member] |
Maximum [Member]
 
 
 
Debt Instrument [Line Items]
 
 
 
Basis spread on variable rate
3.25% 
 
 
Fiscal Quarter Ending December 31, 2014 [Member] |
Fourth Amendment [Member] |
Eurodollar [Member] |
Minimum [Member]
 
 
 
Debt Instrument [Line Items]
 
 
 
Basis spread on variable rate
1.00% 
 
 
Fiscal Quarter Ending December 31, 2014 [Member] |
Fourth Amendment [Member] |
Eurodollar [Member] |
Maximum [Member]
 
 
 
Debt Instrument [Line Items]
 
 
 
Basis spread on variable rate
2.25% 
 
 
Partners' Capital (Units Outstanding) (Details)
In Thousands, unless otherwise specified
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Limited partner common units
30,427 
22,670 
7,414 
General partner units
536 
392 
185 
Series A
 
 
 
Preferred units outstanding
9,210 
5,745 
5,279 
Series B
 
 
 
Preferred units outstanding
1,350 
1,255 
0 
Partners Capital (Details Textual) (USD $)
0 Months Ended 3 Months Ended 12 Months Ended 12 Months Ended 12 Months Ended 0 Months Ended 3 Months Ended 12 Months Ended 3 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 12 Months Ended 0 Months Ended
Oct. 8, 2015
Sep. 15, 2015
Sep. 10, 2015
Jan. 29, 2014
Dec. 31, 2014
Jun. 30, 2014
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Oct. 8, 2015
Sep. 15, 2015
Sep. 10, 2015
Jul. 27, 2015
Aug. 20, 2014
Feb. 5, 2014
Jan. 29, 2014
Dec. 11, 2013
Dec. 31, 2015
Series B
Dec. 31, 2015
General Partner Interest
Dec. 31, 2014
General Partner Interest
Dec. 31, 2013
General Partner Interest
Dec. 31, 2015
General Partner [Member]
Dec. 31, 2013
General Partner [Member]
Feb. 5, 2014
AIM Midstream Holdings [Member]
Feb. 5, 2014
High Point [Member]
Dec. 31, 2015
Series A-2 [Member]
Apr. 15, 2013
Series A
Dec. 31, 2015
Series A
Dec. 31, 2015
Series A
Dec. 31, 2014
Series A
Dec. 31, 2014
Series B
Dec. 31, 2015
Issuance of Preferred Units [Member]
Series A-2 [Member]
Magnolia Infrastructure Partners, LLC [Member]
Apr. 15, 2013
Issuance of Preferred Units [Member]
Series A
High Point [Member]
Aug. 9, 2013
Partnership Interest [Member]
Apr. 15, 2013
Partnership Interest [Member]
High Point [Member]
AIM Midstream Holdings [Member]
Dec. 31, 2014
High Point [Member]
Oct. 14, 2014
Costar Midstream, L.L.C. [Member]
Dec. 31, 2015
Costar Midstream, L.L.C. [Member]
Dec. 31, 2014
Costar Midstream, L.L.C. [Member]
Apr. 15, 2013
High Point [Member]
Apr. 15, 2013
Fourth Amendment [Member]
Revolving Credit Facility [Member]
Series A
Dec. 31, 2015
Series A
Dec. 31, 2014
Series A
Dec. 31, 2015
Series B
Dec. 31, 2014
Series B
Dec. 31, 2013
Series B
Jan. 31, 2014
Series B
Dec. 31, 2015
Series B
Dec. 31, 2014
Series B
Dec. 31, 2015
Dividend Paid [Member]
Series A
Dec. 31, 2014
Dividend Paid [Member]
Series A
Dec. 31, 2013
Dividend Paid [Member]
Series A
Dec. 31, 2015
Dividend Paid [Member]
Series B
Dec. 31, 2014
Dividend Paid [Member]
Series B
Oct. 14, 2014
Limited Partner [Member]
Costar Midstream, L.L.C. [Member]
Jan. 26, 2016
Subsequent Event [Member]
Feb. 12, 2016
Interest Rate Swap [Member]
Subsequent Event [Member]
Subsidiary, Sale of Stock [Line Items]
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Fair value input, option value
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
0.07 
 
9.68 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Issuance of Series A Units
 
 
 
 
 
 
$ 44,768,000 
$ 0 
$ 14,393,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 45,000,000 
 
 
 
 
$ 30,000,000 
 
 
 
 
 
 
 
 
 
 
 
 
$ 0 
$ 30,000,000 
$ 0 
 
 
 
 
 
 
 
 
 
 
 
Discount rate
 
 
 
 
9.50% 
 
10.00% 
 
10.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
18.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Distribution Made to Limited Partner, Distributions Declared, Per Unit, Annualized Basis
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 1.89 
 
Distribution growth rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Accrued and paid-in-kind unitholder distribution for Series A Units
 
 
 
 
 
 
 
 
4,811,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
16,978,000 
13,154,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
General partner interest
 
 
 
 
 
 
1.30% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Limited partner interest
 
 
 
 
 
 
98.70% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Limited partners, units issued
 
 
 
 
22,670,000 
 
30,427,000 
22,670,000 
7,414,000 
151,937 
7,500,000 
7,500,000 
 
4,622,352 
 
3,400,000 
2,568,712 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1,168,225 
 
 
893,830 
466,638 
135,705 
94,923 
86,461 
 
 
 
Partnership cancellation of subordinated units (percent)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
90.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Total Consideration for Issuance of Preferred Units
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
15,000,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Contributed capital
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5,142,857 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Transaction expenses
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2,500,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Payments on long-term debt
 
 
 
 
 
 
(189,150,000)
(250,870,000)
(131,571,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
(12,500,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Incentive Distribution, Distribution Per Unit
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 0.4125 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Distribution made to member or limited partner, distributions paid, conversion price per unit
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 17.50 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Fair value, paid in kind distributions
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1,400,000 
2,200,000 
 
 
 
 
 
 
 
 
Other Ownership Interests, Units Outstanding
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4,526,066 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Incentive Distribution Right Allocation
 
 
 
 
 
 
 
100.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
14.98% 
 
 
 
 
 
 
 
 
 
 
 
 
85.02% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Incentive Distribution Right, After Minimum Quarterly Distributions, Percent
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
48.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Partners' Capital Account, Percentage
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5.00% 
95.00% 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Class of Warrant or Right, Number of Securities Called by Warrants or Rights
 
 
 
 
 
 
 
 
 
 
 
 
 
 
300,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Class of Warrant or Right, Exercise Price of Warrants or Rights
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 0.01 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AggregateOfferingPrice
 
 
 
 
 
 
100,000,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Limited partner common units
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
147,296,000 
0 
147,296,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6,900,000.0 
 
 
EscrowedUnitsReturnedtoPartnership
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1,034,483 
Sale of Stock, Price Per Share
 
 
 
 
 
 
 
 
 
$ 11.31 
 
$ 11.31 
 
$ 25.8075 
 
$ 26.75 
$ 22.47 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Distribution declared per common unit (a)
 
 
 
 
 
$ 0.4625 
$ 1.89 
$ 1.85 
$ 1.75 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 0.4725 
 
Issuance of common units, net of offering costs
1,700,000 
 
81,000,000 
86,900,000 
 
 
 
119,300,000 
54,900,000 
 
 
 
 
 
 
 
 
0 
0 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
General Partners' Capital Account, Period Distribution Amount
 
 
 
 
 
 
1,900,000 
5,700,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Partners' Capital Account, Contributions
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
0 
1,996,000 
5,678,000 
12,500,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
General partners' interest units issued
 
 
 
 
392,000 
 
536,000 
392,000 
185,000 
 
 
 
 
 
 
 
 
 
143,517 
206,810 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Partners' Capital Account, Distribution Per Unit of Limited Partner Interest
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 0.50 
$ 0.50 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Investment Options, Exercise Price
 
$ 15.94 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 17.50 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
CallRightdefinedacquisitionvalue
 
 
 
 
 
 
 
 
 
 
 
 
$ 100,000,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Partners' Capital Account, Units, Sold in Private Placement
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2,571,430 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Partners' Capital Cash Distributions (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Class of Stock [Line Items]
 
 
 
Distributions
$ 53,386 
$ 28,009 
$ 16,120 
Preferred Partner [Member] |
Series A
 
 
 
Class of Stock [Line Items]
 
 
 
Distributions
0 
2,658 
2,375 
Limited Partner [Member]
 
 
 
Class of Stock [Line Items]
 
 
 
Distributions
46,597 
22,656 
8,207 
Limited Party, Subordinated [Member]
 
 
 
Class of Stock [Line Items]
 
 
 
Distributions
0 
0 
5,073 
General Partner [Member]
 
 
 
Class of Stock [Line Items]
 
 
 
Distributions
1,187 
333 
284 
General Partner, Incentive Distribution Rights [Member]
 
 
 
Class of Stock [Line Items]
 
 
 
Distributions
$ 5,602 
$ 2,362 
$ 181 
Earnings per Unit (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
 
 
 
 
 
 
 
 
 
 
 
Net income (loss) from continuing operations
$ (121,634)
$ (4,574)
$ (2,002)
$ 835 
$ (94,261)
$ (2,397)
$ (1,095)
$ 558 
$ (127,375)
$ (97,195)
$ (30,993)
Net income (loss) attributable to noncontrolling interests
(55)
34 
32 
14 
7 
33 
66 
108 
25 
214 
633 
Net income (loss) from continuing operations attributable to the Partnership
 
 
 
 
 
 
 
 
(127,400)
(97,409)
(31,626)
Distributions on Series A preferred units
4,400 
 
 
 
 
 
 
 
16,978 
14,492 
24,117 
Distributions
 
 
 
 
 
 
 
 
53,386 
28,009 
16,120 
General partner's share in undistributed loss
 
 
 
 
 
 
 
 
(2,569)
(1,820)
(1,708)
Net income (loss) from continuing operations available to limited Partners
 
 
 
 
 
 
 
 
(149,972)
(114,995)
(53,783)
Net income (loss) from discontinued operations available to Limited Partners
 
 
 
 
 
 
 
 
(80)
(603)
(2,051)
Net income (loss) available to Limited Partners
 
 
 
 
 
 
 
 
(150,052)
(115,598)
(55,834)
Weighted average number of units used in computation of Limited Partners' net income (loss) per unit (basic and diluted)
 
 
 
 
 
 
 
 
24,983 
13,472 
7,525 
Limited Partners' net income (loss) from continuing operations per unit (basic and diluted)
$ (4.16)
$ (0.48)
$ (0.35)
$ (0.19)
$ (4.98)
$ (0.58)
$ (0.55)
$ (0.31)
$ (6.00)
$ (8.54)
$ (7.15)
Limited Partners' net income (loss) from discontinued operations per unit (basic and diluted)
$ 0.00 
$ 0.00 
$ 0.00 
$ 0.00 
$ 0.00 
$ 0.00 
$ (0.04)
$ (0.01)
$ 0.00 
$ (0.04)
$ (0.27)
Limited partners’ net income (loss) per unit (basic and diluted)
$ (4.16)
$ (0.48)
$ (0.35)
$ (0.19)
$ (4.98)
$ (0.58)
$ (0.59)
$ (0.32)
$ (6.00)
$ (8.58)
$ (7.42)
Series B
 
 
 
 
 
 
 
 
 
 
 
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
 
 
 
 
 
 
 
 
 
 
 
Distributions
 
 
 
 
 
 
 
 
1,373 
2,220 
0 
Blackwater [Member]
 
 
 
 
 
 
 
 
 
 
 
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
 
 
 
 
 
 
 
 
 
 
 
Net income (loss) from continuing operations
 
 
 
 
 
 
 
 
0 
0 
(716)
General Partner [Member]
 
 
 
 
 
 
 
 
 
 
 
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
 
 
 
 
 
 
 
 
 
 
 
Distributions
 
 
 
 
 
 
 
 
7,023 
2,913 
623 
General Partner [Member] |
Dividend Declared [Member]
 
 
 
 
 
 
 
 
 
 
 
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
 
 
 
 
 
 
 
 
 
 
 
Distributions
 
 
 
 
 
 
 
 
$ 6,790 
$ 2,694 
$ 464 
Long-Term Incentive Plan (Unit-based Awards) (Details) (USD $)
In Thousands, except Share data, unless otherwise specified
1 Months Ended 12 Months Ended
Dec. 31, 2015
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Allocated Share-based Compensation Expense
 
$ 3,774 
$ 1,536 
$ 2,094 
Weighted average volatility
 
47.00% 
 
 
Expected dividend yield
 
26.30% 
 
 
Weighted average expected term (in years)
 
3 years 6 months 
 
 
Weighted average risk-free rate
 
1.30% 
 
 
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
 
 
 
 
Outstanding at beginning of period
 
201,132 
 
 
Granted
 
546,329 
 
 
Forfeited
 
(31,298)
 
 
Vested
 
(146,404)
 
 
Outstanding at end of period
569,759 
569,759 
201,132 
 
Outstanding at beginning of period
 
$ 19.85 
 
 
Granted
 
$ 12.25 
 
 
Forfeited
 
$ 15.62 
 
 
Vested
 
$ 18.47 
 
 
Outstanding at end of period
$ 13.15 
$ 13.15 
$ 19.85 
 
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding
 
 
 
 
Outstanding at beginning of period
 
0 
 
 
Granted
200,000 
200,000 
 
 
Forfeited
 
0 
 
 
Vested
 
0 
 
 
Outstanding at end of period
200,000 
200,000 
0 
 
Outstanding at beginning of period
 
$ 0.00 
 
 
Granted
$ 7.50 
$ 7.50 
 
 
Forfeited
 
$ 0.00 
 
 
Vested
 
$ 0.00 
 
 
Outstanding at end of period
$ 7.50 
$ 7.50 
$ 0.00 
 
Performance Shares [Member]
 
 
 
 
Allocated Share-based Compensation Expense
 
$ 500 
 
 
Long Term Incentive Plan (Textual) (Details) (USD $)
1 Months Ended 12 Months Ended 12 Months Ended
Dec. 31, 2015
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Nov. 30, 2015
Jul. 11, 2012
Feb. 11, 2016
Subsequent Event [Member]
Dec. 31, 2015
Performance Shares [Member]
Subsequent Event [Line Items]
 
 
 
 
 
 
 
 
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options
$ 100,000 
$ 100,000 
 
 
 
 
 
 
Equity compensation expense
 
3,774,000 
1,536,000 
2,094,000 
 
 
 
500,000 
Long-term incentive plan, increase in available awards
 
 
 
 
 
871,750 
6,000,000 
 
Long term incentive plan available for future grant
15,484 
15,484 
688,976 
855,089 
 
 
 
 
Grants issued under long term incentive plan
25.00% 
25.00% 
 
 
 
 
 
 
Total fair value of vested units
 
2,600,000 
1,400,000 
2,200,000 
 
 
 
 
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized
5,900,000 
5,900,000 
3,100,000 
900,000 
 
 
 
1,500,000 
Weighted average period cost recognized
 
2 years 9 months 
 
 
 
 
 
 
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested
 
 
 
 
$ 2,000,000 
 
 
 
Granted
200,000 
200,000 
 
 
 
 
 
 
Granted
$ 7.50 
$ 7.50 
 
 
 
 
 
 
Post-Employment Benefits (Details Textual) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
 
 
Defined Benefit Plan, Benefit Obligation
$ 0.6 
$ 0.7 
Defined Benefit Plan, Fair Value of Plan Assets
1.8 
1.7 
Defined Benefit Plan, Net Periodic Benefit Cost
(0.1)
 
2016
$ 0.1 
 
Income Tax (Details) (USD $)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
 
 
 
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest
$ (126,241,000)
$ (96,638,000)
$ (31,488,000)
Effective income tax rate, continuing operations
34.00% 
34.00% 
34.00% 
Operating Loss Carryforwards
19,300,000 
 
 
Net operating loss carryforwards
7,570,000 
4,173,000 
 
Other
493,000 
213,000 
 
Total deferred tax assets
8,063,000 
4,386,000 
 
Property, plant and equipment
13,889,000 
9,112,000 
 
Intangible assets
0 
387,000 
 
Total deferred tax liabilities
13,889,000 
9,499,000 
 
Income Tax Reconciliation, Income Tax Expense (Benefit), at Federal Statutory Income Tax Rate
42,922,000 
32,857,000 
10,706,000 
Partnership loss not subject to income tax
(43,812,000)
(33,216,000)
(10,296,000)
Income not subject to corporate-level tax
0 
0 
222,000 
State and local tax (benefit) expense
(103,000)
(159,000)
71,000 
Other
(141,000)
(39,000)
(208,000)
Income tax (expense) benefit
(1,134,000)
(557,000)
495,000 
Deferred Tax Liabilities, Net
(5,826,000)
(5,113,000)
 
Current income tax benefit (expense)
0 
(10,000)
0 
Deferred income tax benefit (expense)
$ (1,134,000)
$ (547,000)
$ 495,000 
Effective income tax rate
0.90% 
0.60% 
1.60% 
Commitments and Contingencies (Contractual Obligations) (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2015
Future Non Cancelable Commitment [Line Items]
 
2016
$ 10,543 
2017
2,286 
2018
1,173 
2019
1,345 
2020
1,006 
Thereafter
30,086 
Total
46,439 
Operating leases and service contract [Member]
 
Future Non Cancelable Commitment [Line Items]
 
2016
3,721 
2017
2,286 
2018
1,173 
2019
1,345 
2020
1,006 
Thereafter
1,537 
Total
11,068 
ARO [Member]
 
Future Non Cancelable Commitment [Line Items]
 
2016
6,822 
2017
0 
2018
0 
2019
0 
2020
0 
Thereafter
28,549 
Total
$ 35,371 
Commitments and Contingencies (Details Textual) (USD $)
In Millions, except Share data, unless otherwise specified
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Feb. 5, 2014
Loss Contingencies [Line Items]
 
 
 
 
Incentive Distribution Right Allocation
 
100.00% 
 
 
Class of Warrant or Right, Number of Securities Called by Warrants or Rights
 
 
 
300,000 
Class of Warrant or Right, Exercise Price of Warrants or Rights
 
 
 
$ 0.01 
Operating leases
$ 12.0 
$ 5.8 
$ 1.1 
 
High Point [Member]
 
 
 
 
Loss Contingencies [Line Items]
 
 
 
 
Partners' Capital Account, Percentage
 
 
 
95.00% 
AIM Midstream Holdings [Member]
 
 
 
 
Loss Contingencies [Line Items]
 
 
 
 
Partners' Capital Account, Percentage
 
 
 
5.00% 
High Point [Member]
 
 
 
 
Loss Contingencies [Line Items]
 
 
 
 
Incentive Distribution Right Allocation
 
85.02% 
 
 
Related- Party Transactions (Details Textual) (USD $)
12 Months Ended 12 Months Ended 3 Months Ended 0 Months Ended 3 Months Ended 12 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Oct. 8, 2015
Sep. 15, 2015
Sep. 10, 2015
Aug. 20, 2014
Jan. 29, 2014
Dec. 11, 2013
Dec. 31, 2015
American Midstream, LLC [Member]
Dec. 31, 2014
American Midstream, LLC [Member]
Dec. 31, 2013
American Midstream, LLC [Member]
Apr. 15, 2013
High Point [Member]
Apr. 15, 2013
High Point [Member]
Issuance of Preferred Units [Member]
Series A
Apr. 15, 2013
Revolving Credit Facility [Member]
Fourth Amendment [Member]
Series A
Dec. 17, 2013
Blackwater [Member]
Mar. 31, 2014
Blackwater [Member]
Dec. 31, 2013
Blackwater [Member]
Dec. 17, 2013
Blackwater [Member]
Apr. 15, 2013
Blackwater [Member]
Dec. 31, 2015
Limited Partner [Member]
Dec. 31, 2014
Limited Partner [Member]
Dec. 31, 2013
Limited Partner [Member]
Dec. 17, 2013
Limited Partner [Member]
Blackwater [Member]
Dec. 31, 2013
Limited Partner [Member]
Blackwater [Member]
Dec. 31, 2015
Series B
Dec. 31, 2014
Series B
Dec. 31, 2013
Series B
Jan. 31, 2014
Series B
Jan. 31, 2014
Series B
Dec. 31, 2015
Series B
Dec. 31, 2014
Series B
Related Party Transactions (Textual) [Abstract]
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Administrative and operational service expenses
 
 
 
 
 
 
 
 
 
$ 28,700,000 
$ 22,600,000 
$ 14,200,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Cost of business development activities
(1,500,000)
(900,000)
 
 
 
 
 
 
 
(100,000)
(100,000)
(800,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Proceeds from Sale of Other Assets, Investing Activities
3,900,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Related Party Transaction, Purchases from Related Party
300,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Management Fees Revenue
1,400,000 
900,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Related Party Transaction, Due from (to) Related Party
3,800,000 
800,000 
 
 
 
 
 
 
 
 
700,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Issuance of Series A Units
44,768,000 
0 
14,393,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
0 
30,000,000 
0 
 
 
 
 
Total Consideration for Issuance of Preferred Units
 
 
 
 
 
 
 
 
 
 
 
 
15,000,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Contributed capital
 
 
 
 
 
 
 
 
 
 
 
 
 
5,142,857 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Transaction expenses
 
 
 
 
 
 
 
 
 
 
 
 
 
2,500,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Payments on long-term debt
(189,150,000)
(250,870,000)
(131,571,000)
 
 
 
 
 
 
 
 
 
 
 
(12,500,000)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Total identifiable net assets
 
 
 
 
 
 
 
 
 
 
 
 
61,900,000 
 
 
 
 
 
 
22,700,000 
 
 
 
 
 
 
 
 
 
 
 
 
Purchase price of business
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
63,900,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Distributions
53,386,000 
28,009,000 
16,120,000 
 
 
 
 
 
 
 
 
 
 
 
 
 
27,700,000 
27,650,000 
 
 
64,714,000 
39,150,000 
21,628,000 
 
 
1,373,000 
2,220,000 
0 
 
 
 
 
Units issued in business acquisition
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
125,500 
 
 
 
 
 
 
 
 
 
 
 
 
 
General Partner Noncash Distributions
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3,100,000 
(3,052,000)
 
 
 
 
 
 
 
Limited partners, units issued
30,427,000 
22,670,000 
7,414,000 
151,937 
7,500,000 
7,500,000 
4,622,352 
3,400,000 
2,568,712 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1,168,225 
 
 
 
Issuance of Series B Units
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$ 0 
 
 
 
 
 
 
 
 
$ 30,000,000 
$ 1,373,000 
$ 32,220,000 
Reporting Segments (Details) (USD $)
3 Months Ended 12 Months Ended
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Jun. 30, 2013
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Segment information
 
 
 
 
 
 
 
 
 
 
 
 
Revenue
 
 
 
 
 
 
 
 
 
$ 235,034,000 
$ 307,309,000 
$ 294,051,000 
Gain (loss) on commodity derivatives, net
 
 
 
 
 
 
 
 
 
1,324,000 
1,091,000 
28,000 
Total revenue
48,599,000 
55,641,000 
67,509,000 
64,609,000 
80,177,000 
70,305,000 
77,680,000 
80,238,000 
 
236,358,000 
308,400,000 
294,079,000 
Purchases of natural gas, NGLs and condensate
 
 
 
 
 
 
 
 
 
105,883,000 
197,952,000 
215,053,000 
Direct operating expenses
 
 
 
 
 
 
 
 
 
(59,549,000)
(45,702,000)
(32,236,000)
Selling, general and administrative expenses
 
 
 
 
 
 
 
 
 
(27,232,000)
(23,103,000)
(19,079,000)
Equity compensation expense
 
 
 
 
 
 
 
 
 
(3,774,000)
(1,536,000)
(2,094,000)
Depreciation, amortization and accretion expense
 
 
 
 
 
 
 
 
 
 
28,832,000 
29,999,000 
Depreciation, amortization and accretion expense
 
 
 
 
 
 
 
 
 
(38,014,000)
(28,832,000)
(30,002,000)
Total operating expenses
 
 
 
 
 
 
 
 
 
234,452,000 
297,125,000 
298,464,000 
Gross Profit
28,067,000 
29,134,000 
32,304,000 
33,776,000 
36,227,000 
21,332,000 
22,167,000 
23,081,000 
 
123,281,000 
102,807,000 
74,821,000 
Gain (loss) on sale of assets, net
 
 
 
 
 
 
 
 
 
(3,011,000)
(122,000)
0 
Other income (expense)
 
 
 
 
 
 
 
 
 
0 
(670,000)
0 
Loss on impairment of property, plant and equipment
 
 
 
 
(99,900,000)
 
 
 
(15,200,000)
0 
(99,892,000)
(18,155,000)
Goodwill, Impairment Loss
 
 
 
 
 
 
 
 
 
(118,592,000)
0 
0 
Gain (loss) on involuntary conversion of property, plant and equipment
 
 
 
 
 
 
 
 
 
0 
0 
343,000 
Interest expense
 
 
 
 
 
 
 
 
 
14,745,000 
7,577,000 
9,291,000 
Earnings in unconsolidated affiliates
 
 
 
 
 
 
 
 
 
8,201,000 
348,000 
0 
Income tax (expense) benefit
 
 
 
 
 
 
 
 
 
1,134,000 
557,000 
(495,000)
Net income (loss)
 
 
 
 
 
 
 
 
 
(127,455,000)
(97,806,000)
(33,406,000)
Net income (loss) attributable to noncontrolling interests
55,000 
(34,000)
(32,000)
(14,000)
(7,000)
(33,000)
(66,000)
(108,000)
 
(25,000)
(214,000)
(633,000)
Income (loss) from discontinued operations, net of tax
(1,000)
(53,000)
(31,000)
5,000 
(29,000)
(26,000)
(506,000)
(50,000)
 
(80,000)
(611,000)
(2,413,000)
Net income (loss) attributable to the Partnership
(121,580,000)
(4,661,000)
(2,065,000)
826,000 
(94,297,000)
(2,456,000)
(1,667,000)
400,000 
 
(127,480,000)
(98,020,000)
(34,039,000)
Gathering And Processing [Member]
 
 
 
 
 
 
 
 
 
 
 
 
Segment information
 
 
 
 
 
 
 
 
 
 
 
 
Revenue
 
 
 
 
 
 
 
 
 
173,597,000 
203,616,000 
205,179,000 
Gain (loss) on commodity derivatives, net
 
 
 
 
 
 
 
 
 
1,324,000 
1,091,000 
28,000 
Total revenue
 
 
 
 
 
 
 
 
 
174,921,000 
204,707,000 
205,207,000 
Purchases of natural gas, NGLs and condensate
 
 
 
 
 
 
 
 
 
97,580,000 
152,690,000 
168,574,000 
Direct operating expenses
 
 
 
 
 
 
 
 
 
(39,189,000)
(23,783,000)
(14,574,000)
Gross Profit
 
 
 
 
 
 
 
 
 
76,865,000 
50,817,000 
36,985,000 
Transmission [Member]
 
 
 
 
 
 
 
 
 
 
 
 
Segment information
 
 
 
 
 
 
 
 
 
 
 
 
Revenue
 
 
 
 
 
 
 
 
 
43,682,000 
88,189,000 
79,041,000 
Gain (loss) on commodity derivatives, net
 
 
 
 
 
 
 
 
 
0 
0 
0 
Total revenue
 
 
 
 
 
 
 
 
 
43,682,000 
88,189,000 
79,041,000 
Purchases of natural gas, NGLs and condensate
 
 
 
 
 
 
 
 
 
8,303,000 
45,262,000 
46,479,000 
Direct operating expenses
 
 
 
 
 
 
 
 
 
(13,720,000)
(15,577,000)
(13,259,000)
Gross Profit
 
 
 
 
 
 
 
 
 
35,301,000 
42,828,000 
32,408,000 
Terminals [Member]
 
 
 
 
 
 
 
 
 
 
 
 
Segment information
 
 
 
 
 
 
 
 
 
 
 
 
Revenue
 
 
 
 
 
 
 
 
 
17,755,000 
15,504,000 
9,831,000 
Gain (loss) on commodity derivatives, net
 
 
 
 
 
 
 
 
 
0 
0 
0 
Total revenue
 
 
 
 
 
 
 
 
 
17,755,000 
15,504,000 
9,800,000 
Purchases of natural gas, NGLs and condensate
 
 
 
 
 
 
 
 
 
0 
0 
0 
Direct operating expenses
 
 
 
 
 
 
 
 
 
(6,640,000)
(6,342,000)
(4,403,000)
Gross Profit
 
 
 
 
 
 
 
 
 
11,115,000 
9,162,000 
5,428,000 
Commodity Contract [Member]
 
 
 
 
 
 
 
 
 
 
 
 
Segment information
 
 
 
 
 
 
 
 
 
 
 
 
Gain (loss) on commodity derivatives, net
 
 
 
 
 
 
 
 
 
457,000 
(733,000)
200,000 
Gain (Loss) on Derivative Instruments [Member] |
Commodity Contract [Member]
 
 
 
 
 
 
 
 
 
 
 
 
Segment information
 
 
 
 
 
 
 
 
 
 
 
 
Gain (loss) on commodity derivatives, net
 
 
 
 
 
 
 
 
 
$ 1,610,000 
$ 735,000 
$ 1,069,000 
Reporting Segments Reporting Segment (Revenue Earned from Customers that Exceed 10%) (Details)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
100.00% 
100.00% 
100.00% 
Customer A [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
10.00% 
22.00% 
28.00% 
Customer B [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
0.00% 
0.00% 
13.00% 
Customer C [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
0.00% 
12.00% 
12.00% 
Customer D [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
0.00% 
10.00% 
10.00% 
Customer Other [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
90.00% 
56.00% 
37.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Gathering And Processing [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
100.00% 
100.00% 
100.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Transmission [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
100.00% 
100.00% 
100.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Terminals [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
100.00% 
100.00% 
100.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer A [Member] |
Gathering And Processing [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
12.00% 
33.00% 
43.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer B [Member] |
Gathering And Processing [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
0.00% 
12.00% 
19.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer B [Member] |
Terminals [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
13.00% 
20.00% 
17.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer J [Member] |
Gathering And Processing [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
12.00% 
0.00% 
0.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer C [Member] |
Transmission [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
0.00% 
43.00% 
39.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer D [Member] |
Transmission [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
16.00% 
16.00% 
16.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer K [Member] |
Transmission [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
19.00% 
0.00% 
0.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer H [Member] |
Terminals [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
0.00% 
11.00% 
13.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer I [Member] |
Terminals [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
13.00% 
0.00% 
0.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer F [Member] |
Terminals [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
13.00% 
19.00% 
20.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer G [Member] |
Terminals [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
21.00% 
15.00% 
16.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer Other [Member] |
Gathering And Processing [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
76.00% 
55.00% 
38.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer Other [Member] |
Transmission [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
65.00% 
41.00% 
45.00% 
Customer Concentration Risk [Member] |
Revenue [Member] |
Customer Other [Member] |
Terminals [Member]
 
 
 
Segment Reporting Information [Line Items]
 
 
 
Entity-wide revenue by major customer, percentage
40.00% 
35.00% 
34.00% 
Reporting Segments Assets (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2015
Dec. 31, 2014
Segment Reporting Information [Line Items]
 
 
Total assets
$ 891,296 
$ 913,558 
Gathering And Processing [Member]
 
 
Segment Reporting Information [Line Items]
 
 
Total assets
572,824 
686,395 
Transmission [Member]
 
 
Segment Reporting Information [Line Items]
 
 
Total assets
133,870 
132,767 
Terminals [Member]
 
 
Segment Reporting Information [Line Items]
 
 
Total assets
84,449 
68,094 
Other Segments [Member]
 
 
Segment Reporting Information [Line Items]
 
 
Total assets
$ 100,153 
$ 26,302 
Quarterly Financial Data (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Jun. 30, 2013
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
 
 
 
 
 
 
 
 
 
 
 
 
Loss on impairment of goodwill
 
 
 
 
 
 
 
 
 
$ 118,592 
$ 0 
$ 0 
Total revenue
48,599 
55,641 
67,509 
64,609 
80,177 
70,305 
77,680 
80,238 
 
236,358 
308,400 
294,079 
Gross Profit
28,067 
29,134 
32,304 
33,776 
36,227 
21,332 
22,167 
23,081 
 
123,281 
102,807 
74,821 
Operating income (loss)
(123,475)
(1,523)
1,867 
3,434 
(91,633)
(290)
734 
2,450 
 
(119,697)
(88,739)
(22,197)
Net income (loss) from continuing operations
(121,634)
(4,574)
(2,002)
835 
(94,261)
(2,397)
(1,095)
558 
 
(127,375)
(97,195)
(30,993)
Income (loss) from discontinued operations, net of tax
(1)
(53)
(31)
5 
(29)
(26)
(506)
(50)
 
(80)
(611)
(2,413)
Net income (loss) attributable to noncontrolling interests
55 
(34)
(32)
(14)
(7)
(33)
(66)
(108)
 
(25)
(214)
(633)
Net income (loss) attributable to the Partnership
(121,580)
(4,661)
(2,065)
826 
(94,297)
(2,456)
(1,667)
400 
 
(127,480)
(98,020)
(34,039)
General Partner's Interest in net income (loss)
(1,570)
(60)
(25)
10 
(1,232)
(32)
(22)
7 
 
 
 
 
Limited Partners' Interest in net income (loss)
(120,010)
(4,601)
(2,040)
816 
(93,065)
(2,424)
(1,645)
393 
 
 
 
 
Income (Loss) from Continuing Operations, Per Outstanding Limited Partnership Unit, Basic
$ (4.16)
$ (0.48)
$ (0.35)
$ (0.19)
$ (4.98)
$ (0.58)
$ (0.55)
$ (0.31)
 
$ (6.00)
$ (8.54)
$ (7.15)
Limited Partners' net income (loss) from discontinued operations per unit (basic and diluted)
$ 0.00 
$ 0.00 
$ 0.00 
$ 0.00 
$ 0.00 
$ 0.00 
$ (0.04)
$ (0.01)
 
$ 0.00 
$ (0.04)
$ (0.27)
Limited partners’ net income (loss) per unit (basic and diluted)
$ (4.16)
$ (0.48)
$ (0.35)
$ (0.19)
$ (4.98)
$ (0.58)
$ (0.59)
$ (0.32)
 
$ (6.00)
$ (8.58)
$ (7.42)
Loss on impairment of property, plant and equipment
 
 
 
 
$ 99,900 
 
 
 
$ 15,200 
$ 0 
$ 99,892 
$ 18,155