Third Coast Midstream (AMID) 10-Q 10 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2015	Aug. 07, 2015	Dec. 31, 2014
Document Information [Line Items]
Entity Registrant Name	American Midstream Partners, LP
Entity Central Index Key	1,513,965
Document Type	10-Q
Document Period End Date	Jun. 30, 2015
Amendment Flag	false
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		22,762,504
Series A convertible preferred, units, outstanding	8,682,000	8,682,271	5,745,000
Series B [Member]
Document Information [Line Items]
Limited Partners' Capital Account, units outstanding		1,301,282	1,255,000

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 348	$ 499
Accounts receivable	6,263	4,924
Unbilled revenue	18,655	24,619
Risk management assets	1,155	688
Other current assets	8,134	15,554
Current deferred tax assets	5,504	3,086
Total current assets	40,059	49,370
Property, plant and equipment, net	622,590	582,182
Goodwill	134,853	142,236
Intangible assets, net	103,228	106,306
Investment in unconsolidated affiliates	21,935	22,252
Other assets, net	13,982	14,298
Total assets	936,647	916,644
Current liabilities
Accounts payable	15,957	20,326
Accrued gas purchases	9,617	14,326
Accrued expenses and other current liabilities	18,557	25,800
Current portion of long-term debt	737	2,908
Risk management liabilities	69	215
Total current liabilities	44,937	63,575
Asset retirement obligations	35,048	34,645
Other liabilities	287	126
Long-term debt	387,100	372,950
Deferred tax liabilities	11,087	8,199
Total liabilities	478,459	479,495
Series A convertible preferred units (8,682 thousand and 5,745 thousand units issued and outstanding as of June 30, 2015 and December 31, 2014, respectively)	160,373	107,965
Equity and partners' capital
General Partner Interests (411 thousand and 392 thousand units issued and outstanding as of June 30, 2015 and December 31, 2014)	(5,218)	(2,450)
Accumulated other comprehensive income (loss)	(32)	2
Total partners’ capital	293,122	324,467
Noncontrolling interests	4,693	4,717
Total equity and partners' capital	297,815	329,184
Total liabilities, equity and partners' capital	936,647	916,644
Limited Partner Common Units [Member]
Equity and partners' capital
Limited Partner Interests (22,757 thousand and 22,670 thousand units issued and outstanding as of June 30, 2015 and December 31, 2014, respectively)	265,319	294,695
Limited Partner Series B Convertible Units [Member]
Equity and partners' capital
Limited Partner Interests (22,757 thousand and 22,670 thousand units issued and outstanding as of June 30, 2015 and December 31, 2014, respectively)	$ 33,053	$ 32,220

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) - shares	Jun. 30, 2015	Dec. 31, 2014
Series A convertible preferred, units, issued	8,682,000	5,745,000
Series A convertible preferred, units, outstanding	8,682,000	5,745,000
General partner interest, units issued	411,000	392,000
General partner interest units,outstanding	411,000	392,000
Limited Partner Series B Convertible Units [Member]
Limited Partners' Capital Account, Units Issued	1,301,000	1,255,000
Limited Partners' Capital Account, units outstanding	1,301,000	1,255,000
Limited Partner Common Units [Member]
Limited Partners' Capital Account, Units Issued	22,757,000	22,670,000
Limited Partners' Capital Account, units outstanding	22,757,000	22,670,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - Segment [Domain] - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenue		$ 67,198	$ 77,873	$ 131,660	$ 158,241
Gain (loss) on commodity derivatives, net		311	(193)	458	(323)
Total revenue		67,509	77,680	132,118	157,918
Operating expenses:
Purchases of natural gas, NGLs and condensate		33,334	53,818	62,311	109,039
Direct operating expenses		13,967	11,044	27,834	20,005
Selling, general and administrative expenses		5,571	5,637	12,506	11,230
Equity compensation expense		550	435	2,248	795
Depreciation, amortization and accretion expense		9,250	6,012	18,939	13,644
Total operating expenses		62,672	76,946	123,838	154,713
Operating Expenses		62,672	76,946	123,838	154,713
Gain (loss) on sale of assets, net		(2,970)	0	(2,978)	(21)
Operating income (loss)		1,867	734	5,302	3,184
Interest expense		(3,556)	(1,680)	(6,166)	(3,583)
Earnings in unconsolidated affiliates		4	0	171	0
Net income (loss) before income tax (expense) benefit		(1,685)	(946)	(693)	(399)
Income tax (expense) benefit		(317)	(149)	(473)	(138)
Net income (loss) from continuing operations		(2,002)	(1,095)	(1,166)	(537)
Income (loss) from discontinued operations, net of tax		(31)	(506)	(26)	(556)
Net income (loss)		(2,033)	(1,601)	(1,192)	(1,093)
Net income (loss) attributable to noncontrolling interests		32	66	46	174
Net income (loss) attributable to the Partnership		$ (2,065)	$ (1,667)	$ (1,238)	$ (1,267)
Distribution declared per common unit (a)	[1]	$ 0.4725	$ 0.4625	$ 0.9450	$ 0.9150
Income (Loss) from Continuing Operations, Per Outstanding Limited Partnership Unit, Basic, Net of Tax		$ (0.35)	$ (0.55)	$ (0.53)	$ (0.92)
Weighted average number of units used in computation of limited partners’ net (loss) income per unit (basic and diluted)		22,757	11,139	22,730	10,496
Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax		$ (0.35)	$ (0.59)	$ (0.53)	$ (0.97)
General Partner [Member]
Operating expenses:
General Partner's Interest in net income (loss)		$ (25)	$ (22)	$ (14)	$ (15)
Limited Partner [Member]
Operating expenses:
Limited Partners' Interest in net income (loss)		$ (2,040)	$ (1,645)	$ (1,224)	$ (1,252)
[1]	Distributions declared and paid during the three and six months ended June 30, 2015 and 2014 related to prior periods' earnings.

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Net income (loss)	$ (2,033)	$ (1,601)	$ (1,192)	$ (1,093)
Income (loss) from discontinued operations, net of tax	(31)	(506)	(26)	(556)
Comprehensive income (loss)	(2,056)	(1,591)	(1,226)	(1,047)
Less: Comprehensive income (loss) attributable to noncontrolling interests	32	66	46	174
Comprehensive income (loss) attributable to Partnership	(2,088)	(1,657)	(1,272)	(1,221)
Accumulated Other Comprehensive Income (Loss) [Member]
Unrealized gain (loss) on postretirement benefit plan assets and liabilities	$ (23)	$ 10	$ (34)	$ 46

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Changes in Partners' Capital (Unaudited) - USD ($) $ in Thousands	Total	Parent [Member]	General Partner [Member]	Limited Partner [Member]	Series B [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]	Series B [Member]	Series B [Member]Parent [Member]	Series B [Member]Series B [Member]
Partners' Capital	$ 73,839		$ 2,696	$ 71,039	$ 0	$ 104	$ 4,628
Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax	$ (0.97)
Income (Loss) from Continuing Operations, Per Outstanding Limited Partnership Unit, Basic, Net of Tax	$ (0.92)
Partners' Capital		$ (4,212)	146,271	31,052	150	4,547	4,547
Net Income (Loss) Allocated to General Partners			(15)
Net Income (Loss) Allocated to Limited Partners				(1,252)
Net income (loss)	$ (1,093)
Net Income (Loss) Attributable to Parent	(1,267)	(1,267)
Income (loss) from discontinued operations, net of tax	(556)
Less: Comprehensive income (loss) attributable to noncontrolling interests	174
Unitholder contributions		1,276	1,276
Unitholder distributions		(19,285)	(1,192)	(18,093)				$ (1,052)
Issuance and exercise of warrant			(7,164)	7,164
Net distributions to noncontrolling interests							(226)
Acquisition of noncontrolling interests		(21)		(21)			(29)
LTIP vesting	128		(511)	639
LTIP tax netting unit repurchase	(151)	(151)		(151)
Equity based compensation		698	698
Unrealized gain (loss) on postretirement benefit plan assets and liabilities		46				46
Issuance of common units, net of offering costs	86,900	86,904		86,904
Issuance of Series B units									$ 31,052	$ 31,052
Partners' Capital at Jun. 30, 2014		173,261	(4,212)	146,271	31,052	150	4,547
Partners' Capital	$ 324,467		(2,450)	294,695	32,220	2	4,717
Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax	$ (0.53)
Income (Loss) from Continuing Operations, Per Outstanding Limited Partnership Unit, Basic, Net of Tax	$ (0.53)
Partners' Capital	$ 293,122	(5,218)	265,319	33,053	(32)	4,693	4,693
Net Income (Loss) Allocated to General Partners			(14)
Net Income (Loss) Allocated to Limited Partners				(1,224)
Net income (loss)	(1,192)
Net Income (Loss) Attributable to Parent	(1,238)	(1,238)
Income (loss) from discontinued operations, net of tax	(26)
Less: Comprehensive income (loss) attributable to noncontrolling interests	46
Unitholder contributions		376	376
Unitholder distributions		(32,804)	(3,004)	(29,800)				$ (833)
Net distributions to noncontrolling interests							(70)
LTIP vesting		195	(2,178)	2,373
LTIP tax netting unit repurchase	(725)	(725)		(725)
Equity based compensation		2,052	2,052
Unrealized gain (loss) on postretirement benefit plan assets and liabilities		(34)				(34)
Issuance of Series B units									$ 833	$ 833
Partners' Capital at Jun. 30, 2015	$ 293,122	$ 293,122	$ (5,218)	$ 265,319	$ 33,053	$ (32)	$ 4,693

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows (Unaudited) - Equity Component [Domain] - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Net income (loss)	$ (1,192)	$ (1,093)
Depreciation, amortization and accretion expense	18,939	13,644
Amortization of deferred financing costs	667	847
Amortization of weather derivative premium	475	554
Unrealized (gain) loss on commodity derivatives, net	(213)	113
Non-cash compensation	2,294	730
Postretirement expense (benefit)	18	(23)
(Gain) loss on sale of assets, net	2,978	106
Loss on impairment of noncurrent assets held for sale	0	673
Deferred tax expense (benefit)	457	(161)
Accounts receivable	(1,331)	(556)
Unbilled revenue	5,964	(2,083)
Risk management assets and liabilities	(875)	(965)
Other current assets	1,041	1,547
Other assets, net	37	22
Accounts payable	6,200	(851)
Accrued gas purchases	(4,709)	(188)
Accrued expenses and other current liabilities	(1,293)	680
Asset retirement obligations	0	(623)
Other liabilities	163	38
Net cash provided by operating activities	29,620	12,411
Cost of acquisitions, net of cash acquired	7,383	(110,909)
Additions to property, plant and equipment	(79,734)	(13,229)
Proceeds from disposals of property, plant and equipment	3,876	6,202
Investment in unconsolidated affiliate	(626)	0
Return of capital from unconsolidated affiliate	1,329	0
Restricted cash	6,475	0
Net cash used in investing activities	(61,297)	(117,936)
Proceeds from issuance of common units to public, net of offering costs	(348)	86,904
Unitholder contributions	330	1,276
Unitholder distributions	(24,364)	(13,793)
Issuance of Series A Units	45,000	0
Acquisition of noncontrolling interests	0	(8)
Net distributions to noncontrolling interests	(70)	(226)
LTIP tax netting unit repurchase	(725)	(151)
Payment of deferred financing costs	(276)	(154)
Payments on other debt	(2,171)	(1,644)
Borrowings on other debt	0	170
Payments on long-term debt	(123,650)	(75,220)
Borrowings on long-term debt	137,800	80,985
Net cash provided by financing activities	31,526	108,139
Net increase (decrease) in cash and cash equivalents	(151)	2,614
Beginning of period	499	393
End of period	348	3,007
Interest payments, net	5,572	2,718
Increase (decrease) in accrued property, plant and equipment	(16,897)	9,501
Series A [Member]
Accrued paid in-kind unitholder distributions for Series A Units	7,607	5,760
Series B [Member]
Issuance of Series A Units	0	30,000
Accrued paid in-kind unitholder distributions for Series A Units	$ 833	$ 1,052

Organization and Basis of Prese

Organization and Basis of Presentation	6 Months Ended
	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation General American Midstream Partners, LP (the "Partnership", "we", "us", or "our"), 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 in a series 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, fractionating NGLs, transporting oil and storing specialty chemical products through our ownership and operation of twelve gathering systems, five processing facilities, three fractionation facilities, four marine terminal sites, three interstate pipelines, five intrastate pipelines and one oil pipeline. We also own a 66.7% non-operating interest in Main Pass Oil Gathering, LP ("MPOG"), a crude oil gathering and processing system, a 50% undivided, non-operating interest in the Burns Point Plant, a natural gas processing plant, and a 46% non-operated interest in Mesquite, an off-spec condensate fractionation project. Our primary assets, which are strategically located in Alabama, Georgia, Louisiana, Maryland, Mississippi, North Dakota, Tennessee and Texas, provide critical infrastructure that links producers of natural gas, 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 1.7 million barrels of storage capacity across four marine terminal sites. Basis of Presentation These unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles ("GAAP") for interim financial information. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. The year-end balance sheet data was derived from consolidated audited financial statements but does not include disclosures required by GAAP for annual periods. The information furnished herein reflects all normal recurring adjustments that are, in the opinion of management, necessary for a fair statement of financial position and results of operations for the respective interim periods. Our financial results for the three and six months ended June 30, 2015 , are not necessarily indicative of the results that may be expected for the full year ended December 31, 2015 . These unaudited condensed consolidated financial statements should be read in conjunction with our consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2014 (“Annual Report”) filed with the Securities and Exchange Commission (the "SEC") on March 10, 2015. Consolidation Policy The accompanying condensed 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 condensed consolidated financial statements. We hold a 50% undivided interest in the Burns Point natural gas processing plant in which we are responsible for our proportionate share of the costs and expenses of the facility. Our condensed consolidated financial statements reflect our proportionate share of the revenues, expenses, assets and liabilities of this undivided interest. As of June 30, 2015 , we also hold a 92.2% undivided interest in the Chatom Processing and Fractionation facility (the "Chatom System"). Our condensed consolidated financial statements reflect the accounts of the Chatom System and the interests in the Chatom System held by non-affiliated working interest owners are reflected as noncontrolling interests in the Partnership's condensed consolidated financial statements. The Partnership accounts for its 66.7% non-operated interest in MPOG and its 46.0% non-operated interest in Mesquite under the equity method. Use of Estimates When preparing condensed 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 estimates, including assumptions for 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.

Acquisitions and Divestitures

Acquisitions and Divestitures	6 Months Ended
	Jun. 30, 2015
Business Combinations [Abstract]
Acquisitions and Divestitures	Acquisitions and Divestitures 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 representing Limited Partner interests, or 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 under development 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 over 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. During the first quarter of 2015, we reached an agreement on certain working capital matters with the Costar sellers, resulting in a decrease to goodwill of $0.2 million . In the second quarter of 2015, we reached an agreement with the Costar sellers regarding certain capital expenditures that we have incurred, or will incur, that were not known at the time of closing, which resulted in a decrease to goodwill and cash consideration transferred of $7.2 million . 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 based upon their respective fair values as of the acquisition date (in thousands). Fair value of consideration transferred: 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: 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 of $147.3 million differs from the amount determined using 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 common units issued in the transaction was determined using an option pricing model and the following key assumptions: i) the closing unit market price on the day of the acquisition, ii) the contractual holding periods, iii) historical 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 that 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. For the three and six months ended June 30, 2015 , Costar contributed revenue of $24.2 million and $45.6 million , respectively, and net income of $0.6 million and $1.8 million , respectively, attributable to the Partnership's Gathering and Processing segment. 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 acquisition 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 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 gas gathering agreement under which PVA has dedicated certain acreage and related production to the acquired facilities. For the three and six months ended June 30, 2015 , Lavaca contributed revenue of $5.9 million and $11.9 million , respectively, and net income of $2.3 million and $4.5 million , respectively, attributable to the Partnership's Gathering and Processing segment. For the three and six months ended June 30, 2014 , Lavaca contributed revenue of $3.7 million and $6.0 million , respectively, and net income of $0.6 million and $2.2 million , respectively, attributable to the Partnership's Gathering and Processing segment. Other Acquisitions Investment in Unconsolidated Affiliates On August 11, 2014, the Partnership acquired a 66.7% non-operated interest in MPOG, an offshore 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 three and six months ended June 30, 2015 , the Partnership recorded less than $0.1 million and $0.2 million , respectively, in earnings from MPOG. The Partnership received cash distributions of $0.5 million and $1.5 million for the three and six months ended June 30, 2015 , respectively. The excess of the cash distributions received over the earnings recorded from MPOG is classified as a return of capital within the investing section of our consolidated statement 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 our Transmission segment located in offshore Louisiana from Transcontinental Gas Pipe Line Company, LLC, a subsidiary of Williams Partners, LP. for $6.5 million in cash. The acquisition was subject to FERC approval of the seller's application to abandon by sale to us the pipeline facilities 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. Divestitures 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. We received $6.1 million in cash proceeds related to the sale, which approximated its net book value.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the 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. The guidance in ASU 2014-09 is now effective for annual reporting periods beginning after December 15, 2017, including interim periods therein, as a result of the FASB's recent decision to defer the effective date by one year. We are currently evaluating the method of adoption and impact this standard will have on our condensed consolidated financial statements and related disclosures. In February 2015, the FASB issued ASU No. 2015-02, Amendments to the Consolidation Analysis . This guidance amends the analysis that a reporting entity must perform to determine whether it should consolidate certain types of legal entities. ASU 2015-02 is effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2015, and early adoption is permitted. The Partnership is currently evaluating the potential impact this standard will have on its condensed consolidated financial statements and related disclosures. 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. Given the Partnership's debt issuance costs relate to its revolving debt Credit Facility, the Partnership does not anticipate this standard to alter its current accounting for such costs. 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 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 is consistent with our policy and historical presentation of earnings per unit.

Discontinued Operations (Notes)

Discontinued Operations (Notes)	6 Months Ended
	Jun. 30, 2015
Discontinued Operations and Disposal Groups [Abstract]
Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]	Discontinued Operations The Partnership continues to classify the terminal asset in Salisbury, Maryland as held for sale as we are continuing negotiations for the sale of those assets, contingent upon the purchaser’s completion of due diligence. The net book value of the assets and liabilities attributable to the terminal asset comprise less than $0.1 million of Other current assets , $1.2 million of Other assets, net , and less than $0.1 million of Accrued expenses and other current liabilities as of June 30, 2015 and December 31, 2014. We have classified these assets as discontinued operations within our condensed consolidated statement of operations. Accordingly, we reclassified the disposal group's results of operations from our results of continuing operations to Income (loss) from discontinued operations, net of tax in our accompanying condensed consolidated statement of operations for all periods presented. We elected not to present separately the operating, investing and financing cash flows related to the disposal groups in our accompanying condensed consolidated statement of cash flows as this activity was immaterial for all periods presented. The following table presents the revenue, expense and gain (loss) from operations of disposal groups associated with the assets classified as held for sale for the three and six months ended June 30, 2015 and 2014 (in thousands, except per unit amounts): Three months ended June 30, Six months ended June 30, 2015 2014 2015 2014 Revenue $ 10 $ 212 $ 74 $ 449 Expense (61 ) (268 ) (116 ) (545 ) Loss on impairment of property, plant and equipment — (673 ) — (673 ) Loss on sale of assets — (65 ) — (87 ) Income tax benefit 20 288 16 300 Income (loss) from operations of disposal groups, net of tax $ (31 ) $ (506 ) $ (26 ) $ (556 ) Limited partners' net income (loss) per unit from discontinued operations (basic and diluted) $ — $ (0.04 ) $ — $ (0.05 )

Concentration of Credit Risk an

Concentration of Credit Risk and Trade Accounts Receivable	6 Months Ended
	Jun. 30, 2015
Risks and Uncertainties [Abstract]
Concentration of Credit Risk and Trade Account Receivable	Concentration of Credit Risk and Trade Accounts Receivable Our primary assets, which are strategically located in Alabama, Georgia, Louisiana, Maryland, Mississippi, North Dakota, Tennessee and Texas, provide critical infrastructure that links customers of natural gas, 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 as such reduced the concentration which may affect our overall credit risk in that the customers may be similarly affected by changes in economic, regulatory or other factors. We maintain allowances for potentially uncollectible accounts receivable; however, for the three and six months ended June 30, 2015 and 2014 , no allowances on or significant write-offs of accounts receivable were recorded. During the three and six months ended June 30, 2015 , no individual customer accounted for 10% or more of the Partnership's consolidated revenue.

Other Current Assets (Notes)

Other Current Assets (Notes)	6 Months Ended
	Jun. 30, 2015
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Schedule of Other Current Assets	Other current assets consist of the following (in thousands): June 30, December 31, 2015 2014 Prepaid insurance $ 1,922 $ 4,162 Restricted cash — 6,475 Other current assets 6,212 4,917 $ 8,134 $ 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	6 Months Ended
	Jun. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
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. Currently, our commodity derivatives are in the form of swaps. As of June 30, 2015 , the aggregate notional volume of our commodity derivatives was 4.3 million gallons of NGLs, natural gasoline, and crude oil equivalent. 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 June 30, 2015 , we were not required to post collateral with any counterparty. 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 condensed consolidated balance sheets with changes in fair value recognized currently in earnings. Interest Rate Swap We entered into an interest rate swap to manage the impact of the interest rate risk associated with our credit facility, effectively converting a portion of the cash flows related to our long-term variable rate debt into fixed rate cash flows. As of June 30, 2015 , the notional amount of our interest rate swap was $100.0 million . The interest rate swap was entered into with a single counterparty and we were not required to post collateral. The interest rate swap expired August 1, 2015. Weather Derivative In the second quarter of 2015, we entered into a weather derivative 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 in 2015, which are recorded as current Risk management assets on our condensed consolidated balance sheet and are being amortized to Direct operating expenses on a straight-line basis over the term of the contract of one year . Unamortized amounts associated with the weather derivatives were approximately $0.8 million as of June 30, 2015 . As of June 30, 2015 and December 31, 2014 , the value associated with our commodity derivatives, interest rate swap, and weather derivative were recorded in our condensed 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 June 30, December 31, 2014 June 30, December 31, 2014 June 30, December 31, 2014 Current $ 1,155 $ 688 $ — $ — $ 1,155 $ 688 Noncurrent — — — — — — Total assets $ 1,155 $ 688 $ — $ — $ 1,155 $ 688 Current $ — $ — $ (69 ) $ (215 ) $ (69 ) $ (215 ) Noncurrent — — — — — — Total liabilities $ — $ — $ (69 ) $ (215 ) $ (69 ) $ (215 ) For the three and six months ended June 30, 2015 and 2014 , respectively, the realized and unrealized gains (losses) associated with our commodity derivatives, interest rate swap instrument and weather derivative were recorded in our condensed consolidated statements of operations, under the captions as follows (in thousands): Three months ended June 30, Six months ended June 30, Gain (loss) on derivatives Gain (loss) on derivatives Statement of Operations Classification Realized Unrealized Realized Unrealized 2015 Gain (loss) on commodity derivatives, net $ 252 $ 59 $ 391 $ 67 Interest expense (101 ) 98 (203 ) 146 Direct operating expenses (234 ) — (475 ) — Total $ (83 ) $ 157 $ (287 ) $ 213 2014 Gain (loss) on commodity derivatives, net $ (80 ) $ (113 ) $ (182 ) $ (141 ) Interest expense (109 ) 38 (213 ) 28 Direct operating expenses (269 ) — (553 ) — Total $ (458 ) $ (75 ) $ (948 ) $ (113 )

Fair Value Measurement

Fair Value Measurement	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement We believe the carrying amount of cash and cash equivalents, accounts receivable and accounts payable approximates fair value because of the short-term maturity of these instruments. The recorded value of the amounts outstanding under the credit facility 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 facility. 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 in which the transfer occurred. There were no such transfers for the six months ended June 30, 2015 and 2014 . 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 our condensed consolidated balance sheets, that were measured at fair value on a recurring basis as of June 30, 2015 and December 31, 2014 (in thousands): Carrying Amount Estimated Fair Value of the Asset (Liability) Level 1 Level 2 Level 3 Total Commodity derivative instruments, net June 30, 2015 $ 353 $ — $ 353 $ — $ 353 December 31, 2014 286 — 286 — 286 Interest rate swap June 30, 2015 $ (69 ) $ — $ (69 ) $ — $ (69 ) December 31, 2014 (215 ) — (215 ) — (215 ) The unamortized portion of the premium paid to enter the weather derivative described in Note 7 "Derivatives" is included within Risk management assets on our condensed consolidated balance sheet but is not included as part of the above table as it is recorded at amortized carrying cost, not fair value.

Property, Plant and Equipment

Property, Plant and Equipment	6 Months Ended
	Jun. 30, 2015
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment, Net Property, plant and equipment, net, as of June 30, 2015 and December 31, 2014 were as follows (in thousands): Useful Life (in years) June 30, December 31, Land N/A $ 5,282 $ 5,282 Construction in progress N/A 90,085 77,550 Base gas N/A 1,108 1,108 Buildings and improvements 4 to 40 9,708 6,855 Processing and treating plants 8 to 40 81,404 80,837 Pipelines 3 to 40 479,749 451,341 Compressors 4 to 20 30,506 24,548 Dock 20 to 40 8,105 8,072 Tanks, truck rack and piping 20 to 40 32,826 30,079 Equipment 8 to 20 9,474 8,855 Computer software 5 3,856 3,490 Total property, plant and equipment 752,103 698,017 Accumulated depreciation (129,513 ) (115,835 ) Property, plant and equipment, net $ 622,590 $ 582,182 Of the gross property, plant and equipment balances at June 30, 2015 and December 31, 2014 , $104.4 million and $101.9 million , respectively, were related to AlaTenn, Midla and HPGT, our FERC regulated interstate and intrastate assets. Capitalized interest was $0.5 million and $0.1 million for the three months ended June 30, 2015 and 2014 , respectively, and $0.7 million and $0.2 million for the six months ended June 30, 2015 and 2014 , respectively. Depreciation expense was $7.6 million and $4.7 million for the three months ended June 30, 2015 and 2014 , respectively, and $15.5 million and $11.1 million for the six months ended June 30, 2015 and 2014 , respectively.

Goodwill and Intangible Assets,

Goodwill and Intangible Assets, Net (Notes)	6 Months Ended
	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets, Net	Goodwill and Intangible Assets, Net The carrying value of goodwill as of June 30, 2015 and December 31, 2014 , was $134.9 million and $142.2 million , respectively. See Note 3 "Acquisitions and Divestitures" for discussion regarding the change in goodwill from December 31, 2014 to June 30, 2015. Goodwill as of June 30, 2015 consisted of $118.6 million and $16.3 million related to our Gathering and Processing and Terminal segments, respectively. Goodwill as of December 31, 2014 consisted of $125.9 million and $16.3 million related to our Gathering and Processing and Terminal segments, respectively. The goodwill associated with our Gathering and Processing segment relates to the Costar and Lavaca Acquisitions and primarily represent strategic developmental locations to grow the business within the segment. The goodwill associated with our Terminal segment was contributed to the Partnership as part of the Partnerships' acquisition of Blackwater Midstream Holdings LLC ("Blackwater") and other related subsidiaries from an affiliate of HPIP (the "Blackwater Acquisition"). Goodwill was recorded as a result of the excess of the investment by an affiliate of HPIP in Blackwater over the fair market value of the identifiable net assets and customer contracts acquired. Intangible assets, net, consists of customer contracts, relationships and dedicated acreage agreements identified as part of the Costar Acquisition, Lavaca Acquisition and Blackwater Acquisition. These intangible assets have definite lives and are subject to amortization on a straight-line basis over their economic lives, currently ranging from 5 months to thirty years . Intangible assets, net, consist of the following (in thousands): June 30, 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 $ (12,013 ) $ (11,110 ) Customer relationships (1,815 ) (553 ) Dedicated acreage (1,795 ) (882 ) $ (15,623 ) $ (12,545 ) Net carrying amount: Customer contracts $ 88 $ 991 Customer relationships 51,585 52,847 Dedicated acreage 51,555 52,468 $ 103,228 $ 106,306 Amortization expense on our intangible assets totaled $1.5 million and $1.2 million for the three months ended June 30, 2015 and 2014 , respectively, and $3.1 million and $2.1 million for the six months ended June 30, 2015 and 2014 , respectively.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities (Notes)	6 Months Ended
	Jun. 30, 2015
Other Liabilities Disclosure [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities were as follows (in thousands): June 30, December 31, 2015 2014 Accrued capital expenditures $ 8,225 $ 17,134 Accrued expenses 5,587 7,036 Gas imbalances payable 895 1,069 Other 3,850 561 $ 18,557 $ 25,800

Debt Obligations

Debt Obligations	6 Months Ended
	Jun. 30, 2015
Debt Disclosure [Abstract]
Debt Obligations	Debt Obligations Our outstanding borrowings under the credit facility were (in thousands): June 30, December 31, Revolving credit facility $ 387,100 $ 372,950 Other debt 737 2,908 Total debt 387,837 375,858 Less: current portion 737 2,908 Long-term debt $ 387,100 $ 372,950 On September 5, 2014, the Partnership entered into an amended and restated credit agreement (the "Credit Agreement"), which provides for a maximum borrowing equal to $500.0 million , with the ability to further increase the borrowing capacity 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. Our obligations under the Credit Agreement are secured by a first mortgage in favor of the lenders in the majority of our real property. 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 (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 (not less than 2.50 ). The financial covenants in our Credit Agreement may limit the amount available to us for borrowing to less than $500.0 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 six months ended June 30, 2015 and 2014 , the weighted average interest rate on borrowings under the Credit Agreement was approximately 3.90% and 4.18% , respectively. As of June 30, 2015 , our consolidated total leverage was 5.00 and our interest coverage ratio was 8.48 , which were in compliance with the consolidated total leverage ratio and interest coverage ratio tests in accordance with the financial covenants required in the Credit Agreement. At June 30, 2015 and December 31, 2014 , letters of credit outstanding under the Credit Agreement were $1.6 million . Other debt Other debt represents insurance premium financing in the original amount of $3.3 million bearing interest at 3.95% per annum, which is repayable in equal monthly installments of approximately $0.4 million through the third quarter of 2015.

Partners' Capital

Partners' Capital	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Partners' Capital	Partners’ Capital and Convertible Preferred Units Our capital accounts are comprised of approximately 1.2% notional general partner interests and 98.8% limited partner interests. 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 rights held by our General Partner. Our General Partner holds and participates in the distribution of 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 are entitled to vote along with the holders of Limited Partner common units and such units will automatically convert to Limited Partner common units on January 31, 2016. HPIP holds and participates in the distribution 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-2 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 six months ended. 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 Units (such previously existing Series A Units now referred to as the "Series A-1 Units" and, 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. The board of directors of our General Partner has, to date, 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 after January 1, 2016, 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. Equity Offerings On January 29, 2014, the Partnership and certain of its affiliates entered into an 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 Limited Partner 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. Issuance and Exercise of Warrant Effective February 5, 2014, we issued to AIM Midstream Holdings, LLC a warrant to purchase up to 300,000 Limited Partner common units of the Partnership at an exercise price of $0.01 per common unit (the “Warrant”). The Warrant was exercised on February 21, 2014, resulting in the issuance of approximately 300,000 Limited Partner common units. The value of the Warrant of $7.2 million was determined based on the close price of $23.89 of the Limited Partner common units on the exercise date. Equity Outstanding The number of units outstanding as of June 30, 2015 and December 31, 2014 , respectively, were as follows (in thousands): June 30, December 31, Series A convertible preferred units 8,682 5,745 Series B convertible units 1,301 1,255 Limited Partner common units 22,757 22,670 General Partner units 411 392 Distributions We made cash distributions as follows (in thousands): Three months ended June 30, Six months ended June 30, 2015 2014 2015 2014 Series A convertible preferred units — 1,338 — 2,658 Limited Partner common units 10,753 5,152 21,466 10,049 General Partner units 159 76 317 148 General Partners' incentive distribution rights 1,293 527 2,581 937 $ 12,205 $ 7,093 $ 24,364 $ 13,792 The Partnership executed a fourth amendment to its partnership agreement (the "Fourth Amendment"), which became effective March 30, 2015, related to its outstanding Series A Units. As a result of the Fourth Amendment, distributions on Series A Units will be made with paid-in-kind Series A Units, cash or a combination thereof, at the discretion of the board of directors of our General Partner, which began with the distribution for the three months ended June 30, 2014 and will continue 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. At June 30, 2015 , we have accrued $4.2 million for the paid-in-kind Series A Units. The distributions will be made in the third quarter of 2015. Net Income (Loss) attributable to Limited Partner Common Units Net income (loss) is allocated to the General Partner and the limited partners in accordance with their respective ownership percentages, after giving effect to contractual distributions on Series A Units, declared distributions on the Series B Units, common units representing Limited Partner interests and to the General Partner units, including incentive distribution rights. 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 common units during the period. We determined basic and diluted net income (loss) per limited partner unit as follows, (in thousands, except per unit amounts): Three months ended June 30, Six months ended June 30, 2015 2014 2015 2014 Net income (loss) from continuing operations $ (2,002 ) $ (1,095 ) $ (1,166 ) $ (537 ) Less: Net income (loss) attributable to noncontrolling interests 32 66 46 174 Net income (loss) from continuing operations attributable to the Partnership (2,034 ) (1,161 ) (1,212 ) (711 ) Less: Contractual distributions on Series A Units 4,196 3,917 7,607 7,098 Declared distributions on Series B Units 413 560 833 1,052 General partner's distribution 1,452 603 2,899 1,085 General partner's share in undistributed loss (234 ) (149 ) (422 ) (262 ) Net income (loss) from continuing operations available to limited partners (7,861 ) (6,092 ) (12,129 ) (9,684 ) Net income (loss) from discontinued operations available to limited partners (31 ) (499 ) (26 ) (549 ) Net income (loss) available to limited partners $ (7,892 ) $ (6,591 ) $ (12,155 ) $ (10,233 ) Weighted average number of units used in computation of limited partners’ net (loss) income per unit (basic and diluted) 22,757 11,139 22,730 10,496 Limited partners' net loss per common unit Basic and diluted: Loss from continuing operations $ (0.35 ) $ (0.55 ) $ (0.53 ) $ (0.92 ) Loss from discontinued operations — (0.04 ) — (0.05 ) Net loss $ (0.35 ) $ (0.59 ) $ (0.53 ) $ (0.97 )

Long-Term Incentive Plan

Long-Term Incentive Plan	6 Months Ended
	Jun. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Long-Term Incentive Plan	Long-Term Incentive Plan Our General Partner manages our operations and activities and employs personnel who provide support to our operations. The board of directors of our General Partner grants awards under its long-term incentive plan (“LTIP”) for its employees, consultants and directors who perform services for it or its affiliates. At June 30, 2015 and December 31, 2014 , 399,832 and 688,976 units, respectively, were available for future grant under the LTIP. LTIP awards are subject to forfeiture until the vesting date. The LTIP is administered by 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. Although other types of awards are contemplated under the LTIP, all currently outstanding awards are phantom units without distribution equivalent rights. Generally, grants issued under the LTIP vest in increments of 25% on each grant date anniversary and do not contain any vesting conditions other than continued employment requirements. The following table summarizes changes in our unit-based awards during the six months ended June 30, 2015 indicated, in units: Six months ended June 30, 2015 Units Weighted-Average Exercise Price Outstanding at beginning of period 201,132 $ 19.85 Granted 336,613 15.78 Forfeited (8,297 ) 17.24 Vested (126,897 ) 18.84 Outstanding at end of period 402,551 $ 16.82 The fair value of our phantom units, which are subject to equity classification, is based on the fair value of our limited partner units at the grant date. Compensation costs related to these awards, including amortization, for the three months ended June 30, 2015 and 2014 were $0.6 million and $0.4 million , respectively, and for the six months ended June 30, 2015 and 2014 were $2.2 million and $0.8 million , respectively, which are classified as Equity compensation expense in our condensed consolidated statements of operations and the non-cash portion in partners’ capital on our condensed consolidated balance sheets. The total fair value of vested units at the time of vesting was $2.3 million and $0.8 million for the six months ended June 30, 2015 and 2014 , respectively. Equity compensation expense related to unvested awards not yet recognized at June 30, 2015 and 2014 was $6.0 million and $3.8 million , respectively, and the weighted average period over which this cost is expected to be recognized as of June 30, 2015 is approximately 3.2 years .

Income Tax (Notes)

Income Tax (Notes)	6 Months Ended
	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Income Tax	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. However, the State of Texas imposes a margin tax upon the Partnership that is assessed annually against the taxable margin apportioned to Texas. In general, taxes on our net income are borne by our unitholders through the allocation of taxable income. However, one of our subsidiaries, American Midstream Blackwater, LLC, owns a corporate consolidated tax return group which is a separate taxable entity for U.S. federal income tax and state income tax purposes. The provision for income taxes is attributable to the activities of the taxable corporate consolidated tax return group and taxable margin apportioned to Texas. On October 2, 2014, the Partnership received a “Notice of Beginning of Administrative Proceeding” (the “NBAP”) relating to the Internal Revenue Service (the “IRS”) commencing an audit of the Partnership’s 2012 Form 1065 federal tax return. Under IRS regulations, the Partnership was required to communicate the NBAP to all limited partners who hold less than 1% of its outstanding units ("Non-Notice Partners") within 75 days of receipt of the NBAP. The Partnership filed a Current Report on Form 8-K with the SEC on November 19, 2014, furnishing a copy of the NBAP to its Non-Notice Partners. On June 19, 2015, the Partnership received a No Adjustments Letter (the "No Adjustments Letter") relating to the IRS audit of Partnership’s 2012 Form 1065 federal tax return. There were no adjustments proposed by the IRS for the Partnership’s 2012 Form 1065 federal tax return. The Partnership filed a Current Report on Form 8-K with the SEC on June 24, 2015, furnishing a copy of the No Adjustments Letter to its Non-Notice Partners. Income tax expense for the three and six months ended June 30, 2015 was $0.3 million and $0.5 million , respectively, resulting in an effective tax rate of 18.8% and 68.3% , respectively. For the three and six months ended June 30, 2014, income tax expense was $0.1 million and $ 0.1 million , respectively, resulting in an effective tax rate of 15.8% and 34.6% , respectively. The effective tax rates for the three and six months ended June 30, 2015 and June 30, 2014 , differ from the statutory rate primarily due to the portion of the Partnership's income and loss that is not subject to U. S. federal income taxes, as well as transactions between the Partnership and its taxable subsidiary that generate tax deductions for the taxable subsidiary, which are eliminated in the consolidation of Net income (loss) before income tax (expense) benefit .

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
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 certainty, our management believes that the resolution of any of our pending proceedings 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 pipelines, 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 December 11, 2014, American Midstream (Midla), LLC ("Midla"), a subsidiary of the Partnership, filed a Stipulation and Agreement (the "Midla Agreement") which resolved all of the outstanding issues between Midla and its customers regarding its interstate pipeline that traverses Louisiana and Mississippi owned and operated by Midla. The parties involved reached agreement in order to provide continued service to Midla’s customers while addressing safety concerns with the existing pipeline. On April 16, 2015, the FERC approved the Midla Agreement between Midla and its customers allowing Midla to retire the existing 1920s vintage pipeline and replace the existing natural gas service 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. The Midla-Natchez pipeline will replace the Midla pipeline with a new, 12 -inch pipeline extending approximately 50 miles from Winnsboro, Louisiana to Natchez, Mississippi. Subject to FERC approval, construction is expected to commence in the first half of 2016 with service beginning in late 2016. Under the Midla Agreement, Midla will execute long-term agreements to recover its investment in the Midla-Natchez Line.

Related-Party Transactions

Related-Party Transactions	6 Months Ended
	Jun. 30, 2015
Related Party Transactions [Abstract]
Related-Party Transactions	Related-Party Transactions Employees of our General Partner are assigned to work for us. Where directly attributable, the costs of all compensation, benefits expenses and employer expenses for these employees are charged directly by our General Partner to the Partnership, which, in turn, charges the appropriate subsidiary. Our General Partner does not record any profit or margin for the administrative and operational services charged to us. During the three and six months ended June 30, 2015 , administrative and operational services expenses of $7.4 million and $15.0 million , respectively, were charged to us by our General Partner. During the three and six months ended June 30, 2014 , administrative and operational services expenses of $5.1 million and $10.1 million , respectively, were charged to us by our General Partner. For the three and six months ended June 30, 2015 , our General Partner incurred approximately $0.5 million and $0.9 million , respectively, of costs primarily associated with certain business development activities. For the three and six months ended June 30, 2014 , our General Partner incurred costs primarily associated with certain business development activities in amounts equal to approximately $0.2 million and $0.7 million , respectively. For the three and six months ended June 30, 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 $1.1 million and $3.9 million , respectively. 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 affiliates' behalf. During the three and six months ended June 30, 2015 , the Partnership recognized $0.4 million and $0.9 million , in management fee income, respectively, and $0.2 million during the three and six months ended June 30, 2014 that has been recorded as a reduction to Selling, general and administrative expenses .

Reporting Segments

Reporting Segments	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Reporting Segments	Reporting Segments Our operations are located in the United States and are organized into three reporting 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 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, which include local distribution companies, 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 the performance measure utilized by management to monitor the business of each segment. The following tables set forth our segment information for the three and six months ended June 30, 2015 and 2014 (in thousands): Three months ended June 30, 2015 Gathering and Processing Transmission Terminals Total Revenue $ 50,439 $ 12,423 $ 4,336 $ 67,198 Gain (loss) on commodity derivatives, net 311 — — 311 Total revenue 50,750 12,423 4,336 67,509 Operating expenses: Purchases of natural gas, NGL's and condensate 30,272 3,062 — 33,334 Direct operating expenses 9,130 3,253 1,584 13,967 Selling, general and administrative expenses 5,571 Equity compensation expense 550 Depreciation, amortization and accretion expense 9,250 Total operating expenses 62,672 Gain (loss) on sale of assets, net (2,970 ) Interest expense (3,556 ) Earnings in unconsolidated affiliates 4 Income tax benefit (expense) (317 ) Gain (loss) from discontinued operations, net of tax (31 ) Net income (loss) (2,033 ) Less: Net income (loss) attributable to noncontrolling interests 32 Net income (loss) attributable to the Partnership $ (2,065 ) Segment gross margin (a) $ 20,219 $ 9,333 $ 2,752 $ 32,304 Three months ended June 30, 2014 Gathering and Processing Transmission Terminals Total Revenue $ 50,015 $ 23,960 $ 3,898 $ 77,873 Gain (loss) on commodity derivatives, net (193 ) — — (193 ) Total revenue 49,822 23,960 3,898 77,680 Operating expenses: Purchases of natural gas, NGL's and condensate 39,238 14,580 — 53,818 Direct operating expenses 5,746 3,736 1,562 11,044 Selling, general and administrative expenses 5,637 Equity compensation expense 435 Depreciation, amortization and accretion expense 6,012 Total operating expenses 76,946 Interest expense (1,680 ) Income tax benefit (expense) (149 ) Gain (loss) from discontinued operations, net of tax (506 ) Net income (loss) (1,601 ) Less: Net income (loss) attributable to noncontrolling interests 66 Net income (loss) attributable to the Partnership $ (1,667 ) Segment gross margin (a) $ 10,481 $ 9,350 $ 2,336 $ 22,167 Six months ended June 30, 2015 Gathering and Processing Transmission Terminals Total Revenue $ 98,888 $ 24,171 $ 8,601 $ 131,660 Gain (loss) on commodity derivatives, net 458 — — 458 Total revenue 99,346 24,171 8,601 132,118 Operating expenses: Purchases of natural gas, NGL's and condensate 57,590 4,721 — 62,311 Direct operating expenses 18,223 6,432 3,179 27,834 Selling, general and administrative expenses 12,506 Equity compensation expense 2,248 Depreciation, amortization and accretion expense 18,939 Total operating expenses 123,838 Gain (loss) on sale of assets, net (2,978 ) Interest expense (6,166 ) Earnings in unconsolidated affiliates 171 Income tax benefit (expense) (473 ) Gain (loss) from discontinued operations, net of tax (26 ) Net income (loss) (1,192 ) Less: Net income (loss) attributable to noncontrolling interests 46 Net income (loss) attributable to the Partnership $ (1,238 ) Segment gross margin (a) $ 41,265 $ 19,394 $ 5,422 $ 66,081 Six months ended June 30, 2014 Gathering and Processing Transmission Terminals Total Revenue $ 101,641 $ 49,088 $ 7,512 $ 158,241 Gain (loss) on commodity derivatives, net (323 ) — — (323 ) Total revenue 101,318 49,088 7,512 157,918 Operating expenses: Purchases of natural gas, NGL's and condensate 80,359 28,680 — 109,039 Direct operating expenses 9,914 6,854 3,237 20,005 Selling, general and administrative expenses 11,230 Equity compensation expense 795 Depreciation, amortization and accretion expense 13,644 Total operating expenses 154,713 Gain (loss) on sale of assets, net (21 ) Interest expense (3,583 ) Income tax benefit (expense) (138 ) Gain (loss) from discontinued operations, net of tax (556 ) Net income (loss) (1,093 ) Less: Net income (loss) attributable to noncontrolling interests 174 Net income (loss) attributable to the Partnership $ (1,267 ) Segment gross margin (a) $ 20,610 $ 20,363 $ 4,275 $ 45,248 June 30, December 31, 2015 2014 Segment assets: Gathering and Processing $ 684,359 $ 686,395 Transmission 128,291 132,767 Terminals 83,766 71,180 Other (b) 40,231 26,302 Total assets $ 936,647 $ 916,644 (a) Segment gross margin for our Gathering and Processing segment consists of revenue and realized gains or (losses) on commodity derivatives less purchases of natural gas, NGLs and condensate and revenue from construction, operating and maintenance agreements (“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) Other assets not allocable to segments consist of investment in unconsolidated affiliates, corporate leasehold improvements, and other assets.

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2015
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events GP Contribution In connection with the issuance of the Series A-2 Units discussed in Note 13, the General Partner exercised its right to maintain its general partner interest at 1.3% . As a result, we received proceeds of $0.4 million from our General Partner as consideration for 21,975 additional notional general partner units in July of 2015. Distribution On July 23, 2015, we announced a distribution of $0.4725 per unit for the quarter ended June 30, 2015 , or $1.89 per unit on an annualized basis, payable on August 14, 2015 to unitholders of record on August 5, 2015.

Organization and Basis of Pre27

Organization and Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	Nature of Business We are engaged in the business of gathering, treating, processing, and transporting natural gas, fractionating NGLs, transporting oil and storing specialty chemical products through our ownership and operation of twelve gathering systems, five processing facilities, three fractionation facilities, four marine terminal sites, three interstate pipelines, five intrastate pipelines and one oil pipeline. We also own a 66.7% non-operating interest in Main Pass Oil Gathering, LP ("MPOG"), a crude oil gathering and processing system, a 50% undivided, non-operating interest in the Burns Point Plant, a natural gas processing plant, and a 46% non-operated interest in Mesquite, an off-spec condensate fractionation project. Our primary assets, which are strategically located in Alabama, Georgia, Louisiana, Maryland, Mississippi, North Dakota, Tennessee and Texas, provide critical infrastructure that links producers of natural gas, 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 1.7 million barrels of storage capacity across four marine terminal sites.
Basis of Presentation	Basis of Presentation These unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles ("GAAP") for interim financial information. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. The year-end balance sheet data was derived from consolidated audited financial statements but does not include disclosures required by GAAP for annual periods. The information furnished herein reflects all normal recurring adjustments that are, in the opinion of management, necessary for a fair statement of financial position and results of operations for the respective interim periods. Our financial results for the three and six months ended June 30, 2015 , are not necessarily indicative of the results that may be expected for the full year ended December 31, 2015 . These unaudited condensed consolidated financial statements should be read in conjunction with our consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2014 (“Annual Report”) filed with the Securities and Exchange Commission (the "SEC") on March 10, 2015.
Consolidation Policy	Consolidation Policy The accompanying condensed 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 condensed consolidated financial statements. We hold a 50% undivided interest in the Burns Point natural gas processing plant in which we are responsible for our proportionate share of the costs and expenses of the facility. Our condensed consolidated financial statements reflect our proportionate share of the revenues, expenses, assets and liabilities of this undivided interest. As of June 30, 2015 , we also hold a 92.2% undivided interest in the Chatom Processing and Fractionation facility (the "Chatom System"). Our condensed consolidated financial statements reflect the accounts of the Chatom System and the interests in the Chatom System held by non-affiliated working interest owners are reflected as noncontrolling interests in the Partnership's condensed consolidated financial statements. The Partnership accounts for its 66.7% non-operated interest in MPOG and its 46.0% non-operated interest in Mesquite under the equity method.
Use of Estimates	Use of Estimates When preparing condensed 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 estimates, including assumptions for 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.

Acquisitions and Divestitures (

Acquisitions and Divestitures (Tables)	6 Months Ended
	Jun. 30, 2015
Business Acquisition [Line Items]
Schedule of Business Acquisitions, by Acquisition	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 based upon their respective fair values as of the acquisition date (in thousands). Fair value of consideration transferred: 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	Fair Value of assets acquired, liabilities assumed and noncontrolling interest: 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 following table summarizes the final allocation of the purchase price to the assets acquired 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

Discontinued Operations Operati

Discontinued Operations Operation of discontinued operations (Tables)	6 Months Ended
	Jun. 30, 2015
Discontinued Operations and Disposal Groups [Abstract]
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures	The following table presents the revenue, expense and gain (loss) from operations of disposal groups associated with the assets classified as held for sale for the three and six months ended June 30, 2015 and 2014 (in thousands, except per unit amounts): Three months ended June 30, Six months ended June 30, 2015 2014 2015 2014 Revenue $ 10 $ 212 $ 74 $ 449 Expense (61 ) (268 ) (116 ) (545 ) Loss on impairment of property, plant and equipment — (673 ) — (673 ) Loss on sale of assets — (65 ) — (87 ) Income tax benefit 20 288 16 300 Income (loss) from operations of disposal groups, net of tax $ (31 ) $ (506 ) $ (26 ) $ (556 ) Limited partners' net income (loss) per unit from discontinued operations (basic and diluted) $ — $ (0.04 ) $ — $ (0.05 )

Other Current Assets (Tables)

Other Current Assets (Tables)	6 Months Ended
	Jun. 30, 2015
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Current Assets	Other current assets consist of the following (in thousands): June 30, December 31, 2015 2014 Prepaid insurance $ 1,922 $ 4,162 Restricted cash — 6,475 Other current assets 6,212 4,917 $ 8,134 $ 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)

Derivatives (Tables)	6 Months Ended
	Jun. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair value associated with commodity derivative instruments	As of June 30, 2015 and December 31, 2014 , the value associated with our commodity derivatives, interest rate swap, and weather derivative were recorded in our condensed 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 June 30, December 31, 2014 June 30, December 31, 2014 June 30, December 31, 2014 Current $ 1,155 $ 688 $ — $ — $ 1,155 $ 688 Noncurrent — — — — — — Total assets $ 1,155 $ 688 $ — $ — $ 1,155 $ 688 Current $ — $ — $ (69 ) $ (215 ) $ (69 ) $ (215 ) Noncurrent — — — — — — Total liabilities $ — $ — $ (69 ) $ (215 ) $ (69 ) $ (215 )
Realized and unrealized gains (losses) with commodity and interst rate derivative instruments	For the three and six months ended June 30, 2015 and 2014 , respectively, the realized and unrealized gains (losses) associated with our commodity derivatives, interest rate swap instrument and weather derivative were recorded in our condensed consolidated statements of operations, under the captions as follows (in thousands): Three months ended June 30, Six months ended June 30, Gain (loss) on derivatives Gain (loss) on derivatives Statement of Operations Classification Realized Unrealized Realized Unrealized 2015 Gain (loss) on commodity derivatives, net $ 252 $ 59 $ 391 $ 67 Interest expense (101 ) 98 (203 ) 146 Direct operating expenses (234 ) — (475 ) — Total $ (83 ) $ 157 $ (287 ) $ 213 2014 Gain (loss) on commodity derivatives, net $ (80 ) $ (113 ) $ (182 ) $ (141 ) Interest expense (109 ) 38 (213 ) 28 Direct operating expenses (269 ) — (553 ) — Total $ (458 ) $ (75 ) $ (948 ) $ (113 )

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
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 our condensed consolidated balance sheets, that were measured at fair value on a recurring basis as of June 30, 2015 and December 31, 2014 (in thousands): Carrying Amount Estimated Fair Value of the Asset (Liability) Level 1 Level 2 Level 3 Total Commodity derivative instruments, net June 30, 2015 $ 353 $ — $ 353 $ — $ 353 December 31, 2014 286 — 286 — 286 Interest rate swap June 30, 2015 $ (69 ) $ — $ (69 ) $ — $ (69 ) December 31, 2014 (215 ) — (215 ) — (215 )

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	6 Months Ended
	Jun. 30, 2015
Property, Plant and Equipment [Abstract]
Property, plant and equipment, net	Property, plant and equipment, net, as of June 30, 2015 and December 31, 2014 were as follows (in thousands): Useful Life (in years) June 30, December 31, Land N/A $ 5,282 $ 5,282 Construction in progress N/A 90,085 77,550 Base gas N/A 1,108 1,108 Buildings and improvements 4 to 40 9,708 6,855 Processing and treating plants 8 to 40 81,404 80,837 Pipelines 3 to 40 479,749 451,341 Compressors 4 to 20 30,506 24,548 Dock 20 to 40 8,105 8,072 Tanks, truck rack and piping 20 to 40 32,826 30,079 Equipment 8 to 20 9,474 8,855 Computer software 5 3,856 3,490 Total property, plant and equipment 752,103 698,017 Accumulated depreciation (129,513 ) (115,835 ) Property, plant and equipment, net $ 622,590 $ 582,182

Goodwill and Intangible Asset34

Goodwill and Intangible Assets, Net (Tables)	6 Months Ended
	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets	Intangible assets, net, consist of the following (in thousands): June 30, 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 $ (12,013 ) $ (11,110 ) Customer relationships (1,815 ) (553 ) Dedicated acreage (1,795 ) (882 ) $ (15,623 ) $ (12,545 ) Net carrying amount: Customer contracts $ 88 $ 991 Customer relationships 51,585 52,847 Dedicated acreage 51,555 52,468 $ 103,228 $ 106,306

Accrued Expenses and Other Cu35

Accrued Expenses and Other Current Liabilities (Tables)	6 Months Ended
	Jun. 30, 2015
Other Liabilities Disclosure [Abstract]
Schedule of Accrued Liabilities	Accrued expenses and other current liabilities were as follows (in thousands): June 30, December 31, 2015 2014 Accrued capital expenditures $ 8,225 $ 17,134 Accrued expenses 5,587 7,036 Gas imbalances payable 895 1,069 Other 3,850 561 $ 18,557 $ 25,800

Debt Obligations (Tables)

Debt Obligations (Tables)	6 Months Ended
	Jun. 30, 2015
Debt Disclosure [Abstract]
Outstanding borrowings under the credit facility	Our outstanding borrowings under the credit facility were (in thousands): June 30, December 31, Revolving credit facility $ 387,100 $ 372,950 Other debt 737 2,908 Total debt 387,837 375,858 Less: current portion 737 2,908 Long-term debt $ 387,100 $ 372,950

Partners' Capital (Tables)

Partners' Capital (Tables)	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Numbers of units outstanding	The number of units outstanding as of June 30, 2015 and December 31, 2014 , respectively, were as follows (in thousands): June 30, December 31, Series A convertible preferred units 8,682 5,745 Series B convertible units 1,301 1,255 Limited Partner common units 22,757 22,670 General Partner units 411 392 Distributions We made cash distributions as follows (in thousands): Three months ended June 30, Six months ended June 30, 2015 2014 2015 2014 Series A convertible preferred units — 1,338 — 2,658 Limited Partner common units 10,753 5,152 21,466 10,049 General Partner units 159 76 317 148 General Partners' incentive distribution rights 1,293 527 2,581 937 $ 12,205 $ 7,093 $ 24,364 $ 13,792
Schedule of Calulation for Net Income (Loss) Per Limited Partner Unit	We determined basic and diluted net income (loss) per limited partner unit as follows, (in thousands, except per unit amounts): Three months ended June 30, Six months ended June 30, 2015 2014 2015 2014 Net income (loss) from continuing operations $ (2,002 ) $ (1,095 ) $ (1,166 ) $ (537 ) Less: Net income (loss) attributable to noncontrolling interests 32 66 46 174 Net income (loss) from continuing operations attributable to the Partnership (2,034 ) (1,161 ) (1,212 ) (711 ) Less: Contractual distributions on Series A Units 4,196 3,917 7,607 7,098 Declared distributions on Series B Units 413 560 833 1,052 General partner's distribution 1,452 603 2,899 1,085 General partner's share in undistributed loss (234 ) (149 ) (422 ) (262 ) Net income (loss) from continuing operations available to limited partners (7,861 ) (6,092 ) (12,129 ) (9,684 ) Net income (loss) from discontinued operations available to limited partners (31 ) (499 ) (26 ) (549 ) Net income (loss) available to limited partners $ (7,892 ) $ (6,591 ) $ (12,155 ) $ (10,233 ) Weighted average number of units used in computation of limited partners’ net (loss) income per unit (basic and diluted) 22,757 11,139 22,730 10,496 Limited partners' net loss per common unit Basic and diluted: Loss from continuing operations $ (0.35 ) $ (0.55 ) $ (0.53 ) $ (0.92 ) Loss from discontinued operations — (0.04 ) — (0.05 ) Net loss $ (0.35 ) $ (0.59 ) $ (0.53 ) $ (0.97 )

Long-Term Incentive Plan (Table

Long-Term Incentive Plan (Tables)	6 Months Ended
	Jun. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Table summarizes our unit-based awards	The following table summarizes changes in our unit-based awards during the six months ended June 30, 2015 indicated, in units: Six months ended June 30, 2015 Units Weighted-Average Exercise Price Outstanding at beginning of period 201,132 $ 19.85 Granted 336,613 15.78 Forfeited (8,297 ) 17.24 Vested (126,897 ) 18.84 Outstanding at end of period 402,551 $ 16.82

Reporting Segments (Tables)

Reporting Segments (Tables)	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Segment information	The following tables set forth our segment information for the three and six months ended June 30, 2015 and 2014 (in thousands): Three months ended June 30, 2015 Gathering and Processing Transmission Terminals Total Revenue $ 50,439 $ 12,423 $ 4,336 $ 67,198 Gain (loss) on commodity derivatives, net 311 — — 311 Total revenue 50,750 12,423 4,336 67,509 Operating expenses: Purchases of natural gas, NGL's and condensate 30,272 3,062 — 33,334 Direct operating expenses 9,130 3,253 1,584 13,967 Selling, general and administrative expenses 5,571 Equity compensation expense 550 Depreciation, amortization and accretion expense 9,250 Total operating expenses 62,672 Gain (loss) on sale of assets, net (2,970 ) Interest expense (3,556 ) Earnings in unconsolidated affiliates 4 Income tax benefit (expense) (317 ) Gain (loss) from discontinued operations, net of tax (31 ) Net income (loss) (2,033 ) Less: Net income (loss) attributable to noncontrolling interests 32 Net income (loss) attributable to the Partnership $ (2,065 ) Segment gross margin (a) $ 20,219 $ 9,333 $ 2,752 $ 32,304 Three months ended June 30, 2014 Gathering and Processing Transmission Terminals Total Revenue $ 50,015 $ 23,960 $ 3,898 $ 77,873 Gain (loss) on commodity derivatives, net (193 ) — — (193 ) Total revenue 49,822 23,960 3,898 77,680 Operating expenses: Purchases of natural gas, NGL's and condensate 39,238 14,580 — 53,818 Direct operating expenses 5,746 3,736 1,562 11,044 Selling, general and administrative expenses 5,637 Equity compensation expense 435 Depreciation, amortization and accretion expense 6,012 Total operating expenses 76,946 Interest expense (1,680 ) Income tax benefit (expense) (149 ) Gain (loss) from discontinued operations, net of tax (506 ) Net income (loss) (1,601 ) Less: Net income (loss) attributable to noncontrolling interests 66 Net income (loss) attributable to the Partnership $ (1,667 ) Segment gross margin (a) $ 10,481 $ 9,350 $ 2,336 $ 22,167 Six months ended June 30, 2015 Gathering and Processing Transmission Terminals Total Revenue $ 98,888 $ 24,171 $ 8,601 $ 131,660 Gain (loss) on commodity derivatives, net 458 — — 458 Total revenue 99,346 24,171 8,601 132,118 Operating expenses: Purchases of natural gas, NGL's and condensate 57,590 4,721 — 62,311 Direct operating expenses 18,223 6,432 3,179 27,834 Selling, general and administrative expenses 12,506 Equity compensation expense 2,248 Depreciation, amortization and accretion expense 18,939 Total operating expenses 123,838 Gain (loss) on sale of assets, net (2,978 ) Interest expense (6,166 ) Earnings in unconsolidated affiliates 171 Income tax benefit (expense) (473 ) Gain (loss) from discontinued operations, net of tax (26 ) Net income (loss) (1,192 ) Less: Net income (loss) attributable to noncontrolling interests 46 Net income (loss) attributable to the Partnership $ (1,238 ) Segment gross margin (a) $ 41,265 $ 19,394 $ 5,422 $ 66,081 Six months ended June 30, 2014 Gathering and Processing Transmission Terminals Total Revenue $ 101,641 $ 49,088 $ 7,512 $ 158,241 Gain (loss) on commodity derivatives, net (323 ) — — (323 ) Total revenue 101,318 49,088 7,512 157,918 Operating expenses: Purchases of natural gas, NGL's and condensate 80,359 28,680 — 109,039 Direct operating expenses 9,914 6,854 3,237 20,005 Selling, general and administrative expenses 11,230 Equity compensation expense 795 Depreciation, amortization and accretion expense 13,644 Total operating expenses 154,713 Gain (loss) on sale of assets, net (21 ) Interest expense (3,583 ) Income tax benefit (expense) (138 ) Gain (loss) from discontinued operations, net of tax (556 ) Net income (loss) (1,093 ) Less: Net income (loss) attributable to noncontrolling interests 174 Net income (loss) attributable to the Partnership $ (1,267 ) Segment gross margin (a) $ 20,610 $ 20,363 $ 4,275 $ 45,248 June 30, December 31, 2015 2014 Segment assets: Gathering and Processing $ 684,359 $ 686,395 Transmission 128,291 132,767 Terminals 83,766 71,180 Other (b) 40,231 26,302 Total assets $ 936,647 $ 916,644 (a) Segment gross margin for our Gathering and Processing segment consists of revenue and realized gains or (losses) on commodity derivatives less purchases of natural gas, NGLs and condensate and revenue from construction, operating and maintenance agreements (“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) Other assets not allocable to segments consist of investment in unconsolidated affiliates, corporate leasehold improvements, and other assets.

Organization and Basis of Pre40

Organization and Basis of Presentation (Details) bbl in Millions	Jun. 29, 2015mi	Jun. 30, 2015facilitypipelinebillion_cubic_feet_per_daygathering_systemmibbl
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 | gathering_system		12
Number of Processing Facilities		5
Number of Fractionation Facilities		3
Number of Marine Terminal Sites		4
Number of Interstate Pipelines | pipeline		3
Number of Intrastate Pipelines | pipeline		5
Number of Oil Pipelines | pipeline		1
Length Of Pipeline | mi	50	3,000
Volume of Natural Gas, Operating | billion_cubic_feet_per_day		1
Million barrels of storage capacity | bbl		1.7
Noncontrolling Interest, Ownership Percentage by Parent		92.20%
Burns Point Plant [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of voting interests acquired		50.00%
Mesquite [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Equity Method Investment, Ownership Percentage		46.00%
MPOG [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Equity Method Investment, Ownership Percentage		66.70%

Acquisitions and Divestitures L

Acquisitions and Divestitures Lavaca Acquisition (Details) $ in Thousands	Jun. 29, 2015mi	Jan. 31, 2014USD ($)mi	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)mi	Jun. 30, 2014USD ($)	Dec. 31, 2014USD ($)
Business Acquisition [Line Items]
Total revenue			$ 67,509	$ 77,680	$ 132,118	$ 157,918
Length Of Pipeline | mi	50				3,000
Goodwill			134,853		$ 134,853		$ 142,236
Operating Income (Loss)			1,867	734	5,302	3,184
Lavaca [Member]
Business Acquisition [Line Items]
Total revenue			5,900	3,700	11,900	6,000
Business Acquisition, Purchase Price Allocation, Land		$ 2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		$ 59,492
Length Of Pipeline | mi		120
Payments to Acquire Businesses, Gross		$ 104,409
Fair Value Inputs, Discount Rate		10.50%
Business Acquisition, Purchase Price Allocation, Equipment		$ 753
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets		21,350
Goodwill		23,567
Operating Income (Loss)			$ 2,300	$ 600	$ 4,500	$ 2,200
Minimum [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life					5 months
Maximum [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life					30 years
Pipelines [Member] | Lavaca [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		$ 58,737

Acquisitions and Divestitures B

Acquisitions and Divestitures Blackwater Acquisition (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Business Combinations [Abstract]
Total revenue	$ 67,509	$ 77,680	$ 132,118	$ 157,918

Acquisitions and Divestitures M

Acquisitions and Divestitures Madison Divestiture (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2014	Jun. 30, 2015	Jun. 30, 2014
Significant Acquisitions and Disposals [Line Items]
Proceeds from disposals of property, plant and equipment		$ 3,876	$ 6,202
Madison [Member]
Significant Acquisitions and Disposals [Line Items]
Proceeds from disposals of property, plant and equipment	$ 6,100

Acquisitions and Divestitures44

Acquisitions and Divestitures MPOG Acquisition (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Aug. 14, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Aug. 11, 2014
Schedule of Equity Method Investments [Line Items]
Payments to Acquire Equity Method Investments				$ 626	$ 0
Earnings in unconsolidated affiliates		$ 4	$ 0	171	$ 0
Proceeds from Equity Method Investment, Dividends or Distributions, Return of Capital		500		$ 1,500
Equity Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage						66.70%
Payments to Acquire Equity Method Investments	$ 12,000
MPOG [Member]
Schedule of Equity Method Investments [Line Items]
Earnings in unconsolidated affiliates		$ 100

Acquisitions and Divestitures C

Acquisitions and Divestitures Costar Midstream (Details) - USD ($) $ in Thousands, shares in Millions	Oct. 14, 2014	Jan. 31, 2014	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill			$ 134,853			$ 134,853		$ 142,236
Acquisition Working Capital Adjustment			7,200	$ 200
Revenues			67,509		$ 77,680	132,118	$ 157,918
Operating Income (Loss)			1,867		734	5,302	3,184
Costar Midstream, L.L.C. [Member]
Business Acquisition [Line Items]
Percentage of voting interests acquired	100.00%
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Working Capital	$ 8,152
Payments to Acquire Businesses, Gross	$ 258,001
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable, Units	6.9
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	$ 147,296
Business Combination, Consideration Transferred	405,297
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Processing Plants	48,357
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Pipelines	128,799
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Land	1,244
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Buildings	682
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Equipment	9,827
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Construction in Progress	16,146
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	205,055
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Investment in Unconsolidated Affiliate	11,884
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Customer Relationships	53,400
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Dedicated Acreage	32,000
Goodwill	95,025
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value	(219)
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest	405,297
Business Combination, Acquired Receivables, Gross Contractual Amount	$ 11,200
Revenues			24,200			45,600
Operating Income (Loss)			600			1,800
Lavaca [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross		$ 104,409
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Land		2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Equipment		753
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		59,492
Goodwill		$ 23,567
Fair Value Inputs, Discount Rate		10.50%
Revenues			5,900		3,700	11,900	6,000
Operating Income (Loss)			$ 2,300		$ 600	$ 4,500	$ 2,200
Minimum [Member] | Costar Midstream, L.L.C. [Member]
Business Acquisition [Line Items]
Fair Value Inputs, Discount Rate	11.00%
Maximum [Member] | Costar Midstream, L.L.C. [Member]
Business Acquisition [Line Items]
Fair Value Inputs, Discount Rate	16.00%

Acquisitions and Divestitures W

Acquisitions and Divestitures Williams Acquisition (Details) $ in Millions	Mar. 31, 2014USD ($)
Williams [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	$ 6.5

Acquisitions and Divestitures E

Acquisitions and Divestitures Eloi Bay Divestiture (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Jun. 01, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Net	$ 622,590		$ 582,182
Eloi Bay [Member]
Property, Plant and Equipment [Line Items]
Significant Acquisitions and Disposals, Gain (Loss) on Sale or Disposal, Net of Tax		$ 3,000
Property, Plant and Equipment, Net		$ 3,000

Discontinued Operations (Detail

Discontinued Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue	$ 10	$ 212	$ 74	$ 449
Disposal Group, Including Discontinued Operation, Operating Expense	(61)	(268)	(116)	(545)
Disposal Group, Including Discontinued Operation, Impairment	0	(673)	0	(673)
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	0	(65)	0	(87)
Discontinued Operation, Tax Effect of Discontinued Operation	20	288	16	300
Income (loss) from discontinued operations, net of tax	$ (31)	$ (506)	$ (26)	$ (556)
Income (loss) from discontinued operations	$ 0	$ (0.04)	$ 0	$ (0.05)
Blackwater [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Other Assets, Current	$ 100		$ 100
Noncurrent assets held for sale, net	1,200		1,200
Current liabilities held for sale	$ 100		$ 100

Other Current Assets (Details)

Other Current Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid insurance	$ 1,922	$ 4,162
Restricted cash	0	6,475
Other current assets	6,212	4,917
Other Assets, Current	$ 8,134	$ 15,554

Derivatives (Fair Value of Comm

Derivatives (Fair Value of Commodity Derivatives) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Derivative [Line Items]
Gross Risk Management Assets	$ 1,155	$ 688
Gross Risk Management Liabilities	0	0
Net Risk Management Assets (Liabilities)	1,155	688
Gross Risk Management Assets	0	0
Gross Risk Management Liabilities	(69)	(215)
Net Risk Management Assets (Liabilities)	(69)	(215)
Risk Management Assets [Member] | Commodity derivatives [Member]
Derivative [Line Items]
Gross Risk Management Assets	1,155	688
Gross Risk Management Liabilities	0	0
Net Risk Management Assets (Liabilities)	1,155	688
Risk Management Assets - Long Term [Member] | Commodity derivatives [Member]
Derivative [Line Items]
Gross Risk Management Assets	0	0
Gross Risk Management Liabilities	0	0
Net Risk Management Assets (Liabilities)	0	0
Risk Management Liabilities [Member] | Commodity derivatives [Member]
Derivative [Line Items]
Gross Risk Management Assets	0	0
Gross Risk Management Liabilities	(69)	(215)
Net Risk Management Assets (Liabilities)	(69)	(215)
Risk Management Liabilities - Long Term [Member] | Commodity derivatives [Member]
Derivative [Line Items]
Gross Risk Management Assets	0	0
Gross Risk Management Liabilities	0	0
Net Risk Management Assets (Liabilities)	$ 0	$ 0

Derivatives (Realized and Unrea

Derivatives (Realized and Unrealized Gains (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 311	$ (193)	$ 458	$ (323)
Commodity derivatives [Member]
Derivatives, Fair Value [Line Items]
Derivative, Loss on Derivative	(83)	(458)	(287)	(948)
Gain on commodity derivatives, net	157	(75)	213	(113)
Gain (Loss) on Derivative Instruments [Member] | Commodity derivatives [Member]
Derivatives, Fair Value [Line Items]
Derivative, Gain (Loss) on Derivative, Net	252	(80)	391	(182)
Gain on commodity derivatives, net	59	(113)	67	(141)
Interest Expense [Member] | Commodity derivatives [Member]
Derivatives, Fair Value [Line Items]
Derivative, Loss on Derivative	(101)	(109)	(203)	(213)
Gain on commodity derivatives, net	98	38	146	28
Other Income [Member] | Commodity derivatives [Member]
Derivatives, Fair Value [Line Items]
Derivative, Loss on Derivative	(234)	(269)	(475)	(553)
Gain on commodity derivatives, net	$ 0	$ 0	$ 0	$ 0

Derivatives (Details Textual)

Derivatives (Details Textual) gal in Millions	6 Months Ended
	Jun. 30, 2015USD ($)gal	Jun. 30, 2014USD ($)
Derivative [Line Items]
Aggregate notional volume of our commodity derivative | gal	4.3
Amortization of weather derivative premium	$ 475,000	$ 554,000
Interest Rate Swap [Member]
Derivative [Line Items]
Notional amount of interest rate swap	100,000,000
Weather Contract [Member]
Derivative [Line Items]
Potential proceeds from derivative contract	10,000,000
Fair value of derivative	0
Payment for weather derivative premium	$ (900,000)
Derivative term of contract	1 year
Amortization of weather derivative premium	$ 800,000

Fair Value Measurement (Details

Fair Value Measurement (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Commodity derivative instruments, net	$ 353	$ 286
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Commodity derivative instruments, net	(69)	(215)
Estimate of Fair Value Measurement [Member] | Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Commodity derivative instruments, net	353	286
Estimate of Fair Value Measurement [Member] | Commodity Contract [Member] | Level 1 [Member]
Derivatives, Fair Value [Line Items]
Commodity derivative instruments, net	0	0
Estimate of Fair Value Measurement [Member] | Commodity Contract [Member] | Level 2 [Member]
Derivatives, Fair Value [Line Items]
Commodity derivative instruments, net	353	286
Estimate of Fair Value Measurement [Member] | Commodity Contract [Member] | Level 3 [Member]
Derivatives, Fair Value [Line Items]
Commodity derivative instruments, net	0	0
Estimate of Fair Value Measurement [Member] | Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Commodity derivative instruments, net	(69)	(215)
Estimate of Fair Value Measurement [Member] | Interest Rate Swap [Member] | Level 1 [Member]
Derivatives, Fair Value [Line Items]
Commodity derivative instruments, net	0	0
Estimate of Fair Value Measurement [Member] | Interest Rate Swap [Member] | Level 2 [Member]
Derivatives, Fair Value [Line Items]
Commodity derivative instruments, net	(69)	(215)
Estimate of Fair Value Measurement [Member] | Interest Rate Swap [Member] | Level 3 [Member]
Derivatives, Fair Value [Line Items]
Commodity derivative instruments, net	$ 0	$ 0

Property, Plant and Equipment54

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation	$ (129,513)	$ (115,835)
Property, plant and equipment, net	622,590	582,182
Land [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	5,282	5,282
Construction in progress [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	90,085	77,550
Base gas [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	1,108	1,108
Buildings and improvements [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	9,708	6,855
Processing and treating plants [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	81,404	80,837
Pipelines [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	479,749	451,341
Compressors [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	30,506	24,548
Dock [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	8,105	8,072
Tanks, truck rack and piping [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	32,826	30,079
Equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	9,474	8,855
Computer software [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	$ 3,856	3,490
Property plant and equipment in useful life	5 years
Property, Plant And Equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	$ 752,103	$ 698,017
Maximum [Member] | Buildings and improvements [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	40 years
Maximum [Member] | Processing and treating plants [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	40 years
Maximum [Member] | Pipelines [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	40 years
Maximum [Member] | Compressors [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	20 years
Maximum [Member] | Dock [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	40 years
Maximum [Member] | Tanks, truck rack and piping [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	40 years
Maximum [Member] | Equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	20 years
Minimum [Member] | Buildings and improvements [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	4 years
Minimum [Member] | Processing and treating plants [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	8 years
Minimum [Member] | Pipelines [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	3 years
Minimum [Member] | Compressors [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	4 years
Minimum [Member] | Dock [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	20 years
Minimum [Member] | Tanks, truck rack and piping [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	20 years
Minimum [Member] | Equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	8 years

Property, Plant and Equipment55

Property, Plant and Equipment (Details Textual) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Capitalized interest	$ 0.5	$ 0.1	$ 0.7	$ 0.2
Depreciation	7.6	$ 4.7	15.5	$ 11.1
AlaTenn system [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$ 104.4		$ 104.4		$ 101.9

Goodwill and Intangible Asset56

Goodwill and Intangible Assets, Net (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Goodwill	$ 134,853			$ 134,853		$ 142,236
Acquisition Working Capital Adjustment	7,200	$ 200
Amortization of Intangible Assets	1,500		$ 1,200	3,100	$ 2,100
Gathering And Processing [Member]
Segment Reporting Information [Line Items]
Goodwill	118,600			118,600		125,900
Terminals [Member]
Segment Reporting Information [Line Items]
Goodwill	$ 16,300			$ 16,300		$ 16,300
Minimum [Member]
Segment Reporting Information [Line Items]
Finite-Lived Intangible Asset, Useful Life				5 months
Maximum [Member]
Segment Reporting Information [Line Items]
Finite-Lived Intangible Asset, Useful Life				30 years

Goodwill and Intangible Asset57

Goodwill and Intangible Assets, Net Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 1,500	$ 1,200	$ 3,100	$ 2,100
Goodwill	134,853		134,853		$ 142,236
Gross carrying amount:	118,851		118,851		118,851
Accumulated amortization:	(15,623)		(15,623)		(12,545)
Net carrying amount:	103,228		103,228		106,306
Customer Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount:	12,101		12,101		12,101
Accumulated amortization:	(12,013)		(12,013)		(11,110)
Net carrying amount:	88		88		991
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount:	53,400		53,400		53,400
Accumulated amortization:	(1,815)		(1,815)		(553)
Net carrying amount:	51,585		51,585		52,847
Dedicated Acreage [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount:	53,350		53,350		53,350
Accumulated amortization:	(1,795)		(1,795)		(882)
Net carrying amount:	$ 51,555		$ 51,555		$ 52,468

Accrued Expenses and Other Cu58

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Other Liabilities Disclosure [Abstract]
Accrued capital expenditures	$ 8,225	$ 17,134
Accrued expenses	5,587	7,036
Gas imbalances payable	895	1,069
Other	3,850	561
Accrued expenses and other current liabilities	$ 18,557	$ 25,800

Debt Obligations (Details)

Debt Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
Line of Credit Facility, Amount Outstanding Limit	$ 500,000
Revolving credit facility	387,100	$ 372,950
Other debt	737	2,908
Total debt	387,837	375,858
Less: current portion	737	2,908
Long-term debt	$ 387,100	$ 372,950

Debt Obligations (Details Textu

Debt Obligations (Details Textual) $ in Thousands	6 Months Ended
	Jun. 30, 2015USD ($)	Dec. 31, 2014USD ($)	Jun. 30, 2014
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding Limit	$ 500,000
Long-Term Debt (Textual) [Abstract]
Letter of credit outstanding	1,600	$ 1,600
Revolving credit facility	$ 387,100	$ 372,950
Ratio of Indebtedness to Net Capital	5
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.50%
Debt Instrument, Interest Coverage Ratio	8.48
Debt, Weighted Average Interest Rate	3.90%		4.18%
Proceeds from (Payments for) Other Financing Activities	$ 3,300
Debt Instrument, Periodic Payment	$ 400
Maximum [Member]
Long-Term Debt (Textual) [Abstract]
Ratio of Indebtedness to Net Capital	4.75
Ratio of indebtedness to net capital, after permitted acquisition	5.25
Minimum [Member]
Long-Term Debt (Textual) [Abstract]
Debt Instrument, Interest Coverage Ratio	2.50
Federal Funds [Member]
Long-Term Debt (Textual) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	0.50%
Eurodollar [Member]
Long-Term Debt (Textual) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	1.00%
Insurance Premium Financing [Member]
Long-Term Debt (Textual) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	3.95%
Fiscal Quarter Ending December 31, 2014 [Member] | Debt Instrument, Fourth Amendment [Member] | Base Rate [Member] | Maximum [Member]
Long-Term Debt (Textual) [Abstract]
Debt Instrument, Basis Spread on Variable Rate	3.25%
Fiscal Quarter Ending December 31, 2014 [Member] | Debt Instrument, Fourth Amendment [Member] | Base Rate [Member] | Minimum [Member]
Long-Term Debt (Textual) [Abstract]
Debt Instrument, Basis Spread on Variable Rate	2.00%
Fiscal Quarter Ending December 31, 2014 [Member] | Debt Instrument, Fourth Amendment [Member] | Eurodollar [Member] | Maximum [Member]
Long-Term Debt (Textual) [Abstract]
Debt Instrument, Basis Spread on Variable Rate	2.25%
Fiscal Quarter Ending December 31, 2014 [Member] | Debt Instrument, Fourth Amendment [Member] | Eurodollar [Member] | Minimum [Member]
Long-Term Debt (Textual) [Abstract]
Debt Instrument, Basis Spread on Variable Rate	1.00%

Partners' Capital (Details)

Partners' Capital (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Aug. 07, 2015	Jul. 27, 2015	Dec. 31, 2014	Jan. 29, 2014
Limited Partners' Capital Account, Units Issued								3,400,000
Series A convertible preferred, units, outstanding	8,682,000		8,682,000		8,682,271		5,745,000
General partner interest units	411,000		411,000				392,000
Sale of Stock, Price Per Share								$ 26.75
Issuance of common units, net of offering costs				$ 86,900
Payments of Capital Distribution	$ 12,205	$ 7,093	$ 24,364	13,792
AIM Midstream Holdings No. of units outstanding [Member]
Limited Partners' Capital Account, units outstanding							22,670,000
Limited partner subordinated units							392,000
Series B [Member]
Unitholder distributions	$ 413	560	$ 833	1,052
Limited Partners' Capital Account, units outstanding					1,301,282		1,255,000
Limited Partner Series B Convertible Units [Member]
Limited Partners' Capital Account, Units Issued	1,301,000		1,301,000				1,255,000
Limited Partners' Capital Account, units outstanding	1,301,000		1,301,000				1,255,000
Limited Partner Common Units [Member]
Limited Partners' Capital Account, Units Issued	22,757,000		22,757,000				22,670,000
Limited Partners' Capital Account, units outstanding	22,757,000		22,757,000				22,670,000
Limited Partner [Member]
Unitholder distributions	$ 10,753	5,152	$ 21,466	10,049
General Partner [Member]
Unitholder distributions	159	76	317	148
General Partner, Incentive Distribution Rights [Member]
Unitholder distributions	1,293	527	2,581	937
Series A [Member] | Preferred Partner [Member]
Unitholder distributions	$ 0	$ 1,338	$ 0	$ 2,658
Subsequent Event [Member]
CallRightdefinedacquisitionvalue						$ 100,000

Partners Capital (Details Textu

Partners Capital (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	Jul. 27, 2015	Feb. 21, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014	Feb. 05, 2014	Jan. 29, 2014
Subsidiary, Sale of Stock [Line Items]
Warrants Not Settleable in Cash, Fair Value Disclosure		$ 23.89
Partners Capital (Textual) [Abstract]
General partner interest					1.20%
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest					98.80%
Limited Partners' Capital Account, Units Issued									3,400,000
Sale of Stock, Price Per Share									$ 26.75
Issuance of common units, net of offering costs						$ 86,900
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		300,000						300,000
Issuance and exercise of warrant		$ 7,200
Class of Warrant or Right, Exercise Price of Warrants or Rights								$ 0.01
Fair Value, Paid In Kind Distributions, Aggregate					$ 4,200
Partnership Interest [Member]
Partners Capital (Textual) [Abstract]
Other Ownership Interests, Units Outstanding							392,000
Limited Partner [Member]
Subsidiary, Sale of Stock [Line Items]
Unitholder distributions					29,800	18,093
Partners Capital (Textual) [Abstract]
Issuance of common units, net of offering costs						86,904
Issuance and exercise of warrant						7,164
General Partner [Member]
Subsidiary, Sale of Stock [Line Items]
Unitholder distributions					3,004	1,192
Partners Capital (Textual) [Abstract]
Issuance and exercise of warrant						(7,164)
Series B [Member]
Subsidiary, Sale of Stock [Line Items]
Unitholder distributions			$ 413	$ 560	$ 833	$ 1,052
Subsequent Event [Member]
Partners Capital (Textual) [Abstract]
Preferred Stock, Call or Exercise Features	$ 17.50
CallRightdefinedacquisitionvalue	$ 100,000
Issuance of Preferred Units [Member] | Series A [Member] | Magnolia Infrastructure Partners, LLC [Member]
Partners Capital (Textual) [Abstract]
Partners' Capital Account, Units, Sold in Private Placement					2,571,430
Partners' Capital Account, Private Placement of Units					$ 45,000

Partners' Capital (Calculation

Partners' Capital (Calculation of Net Income (Loss) Per Limited Partner Unit) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income (loss)	$ (2,033)	$ (1,601)	$ (1,192)	$ (1,093)
Income (loss) from discontinued operations, net of tax	(31)	(506)	(26)	(556)
Net income (loss) from continuing operations	(2,002)	(1,095)	(1,166)	(537)
Less: Comprehensive income (loss) attributable to noncontrolling interests	32	66	46	174
Income (Loss) from Continuing Operations Attributable to Parent	(2,034)	(1,161)	(1,212)	(711)
Temporary Equity, Dividends, Adjustment	4,196	3,917	7,607	7,098
General Partners' Capital Account, Period Undistributed Income (Loss) From Continuing Operations, Amount	(234)	(149)	(422)	(262)
Net income (loss) from continuing operations available to limited partners	(7,861)	(6,092)	(12,129)	(9,684)
Net income (loss) from discontinued operations available to limited partners	(31)	(499)	(26)	(549)
Net income (loss) available to limited partners	$ (7,892)	$ (6,591)	$ (12,155)	$ (10,233)
Weighted average number of units used in computation of limited partners’ net (loss) income per unit (basic and diluted)	22,757	11,139	22,730	10,496
Income (Loss) from Continuing Operations, Per Outstanding Limited Partnership Unit, Basic, Net of Tax	$ (0.35)	$ (0.55)	$ (0.53)	$ (0.92)
Income (loss) from discontinued operations	0	(0.04)	0	(0.05)
Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax	$ (0.35)	$ (0.59)	$ (0.53)	$ (0.97)
Series B [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
General partner's distribution	$ (413)	$ (560)	$ (833)	$ (1,052)
General Partner [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
General partner's distribution			(3,004)	(1,192)
Dividend Declared [Member] | General Partner [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
General partner's distribution	$ (1,452)	$ (603)	$ (2,899)	$ (1,085)

Long-Term Incentive Plan (Detai

Long-Term Incentive Plan (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Unit-Based Award
Equity compensation expense	$ 550	$ 435	$ 2,248	$ 795
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	399,832		399,832		688,976
Grants Issued Under Long Term Incentive Plan	25.00%		25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			$ 2,300	800
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 6,000	$ 3,800	$ 6,000	$ 3,800
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 16.82		$ 16.82		$ 19.85
Table Summarizes Unit Based Awards
Outstanding, Beginning period			201,132,000
Granted			336,613,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price			$ 15.78
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period			(8,297,000)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price			$ 17.24
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period			(126,897,000)
LTIP vesting, Shares			$ (18.84)
Outstanding, Ending period	402,551,000		402,551,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			3 years 2 months

Income Tax (Details)

Income Tax (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Tax Disclosure [Abstract]
Income tax (expense) benefit	$ (317)	$ (149)	$ (473)	$ (138)
Effective Income Tax Rate, Continuing Operations	(18.80%)	(15.80%)	(68.30%)	(34.60%)

Commitments and Contingencies C

Commitments and Contingencies Commitments and Contingencies (Details)	Jun. 29, 2015mi	Jun. 30, 2015inmi
Commitments and Contingencies Disclosure [Abstract]
Circumferenceofpipe | in		12
Length Of Pipeline	50	3,000

Related- Party Transactions (De

Related- Party Transactions (Details Textual) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Related Party Transactions (Textual) [Abstract]
Proceeds from Sale of Other Assets	$ 1.1		$ 3.9
Management Fees Revenue	0.4		0.9	$ 0.2
American Midstream, L.L.C [Member]
Related Party Transaction [Line Items]
General and Administrative Expense	7.4	$ 5.1	15	10.1
Related Party Transactions (Textual) [Abstract]
Business Development	$ 0.5	$ 0.2	$ 0.9	$ 0.7

Reporting Segments (Details)

Reporting Segments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Segment Reporting, Revenue Reconciling Item [Line Items]
Segment assets:	$ 936,647		$ 936,647		$ 916,644
Segment information
Revenue	67,198	$ 77,873	131,660	$ 158,241
Gain (loss) on commodity derivatives, net	311	(193)	458	(323)
Total revenue	67,509	77,680	132,118	157,918
Purchases of natural gas, NGLs and condensate	33,334	53,818	62,311	109,039
Direct operating expenses	13,967	11,044	27,834	20,005
Selling, general and administrative expenses	5,571	5,637	12,506	11,230
Equity compensation expense	550	435	2,248	795
Depreciation, amortization and accretion expense	9,250	6,012	18,939	13,644
Total operating expenses	62,672	76,946	123,838	154,713
Gain (loss) on sale of assets, net	(2,970)	0	(2,978)	(21)
Income (loss) from discontinued operations, net of tax	(31)	(506)	(26)	(556)
Interest expense	(3,556)	(1,680)	(6,166)	(3,583)
Earnings in unconsolidated affiliates	4	0	171	0
Income tax (expense) benefit	(317)	(149)	(473)	(138)
Net income (loss)	(2,033)	(1,601)	(1,192)	(1,093)
Less: Comprehensive income (loss) attributable to noncontrolling interests	32	66	46	174
Net income (loss) attributable to the Partnership	(2,065)	(1,667)	(1,238)	(1,267)
Segment gross margin	32,304	22,167	66,081	45,248
Gathering And Processing [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Segment assets:	684,359		684,359		686,395
Transmission [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Segment assets:	128,291		128,291		132,767
Gathering and Processing reporting segment [Member]
Segment information
Revenue	50,439	50,015	98,888	101,641
Gain (loss) on commodity derivatives, net	311	(193)	458	(323)
Total revenue	50,750	49,822	99,346	101,318
Purchases of natural gas, NGLs and condensate	30,272	39,238	57,590	80,359
Direct operating expenses	9,130	5,746	18,223	9,914
Segment gross margin	20,219	10,481	41,265	20,610
Transmission reporting segment [Member]
Segment information
Revenue	12,423	23,960	24,171	49,088
Gain (loss) on commodity derivatives, net	0	0	0	0
Total revenue	12,423	23,960	24,171	49,088
Purchases of natural gas, NGLs and condensate	3,062	14,580	4,721	28,680
Direct operating expenses	3,253	3,736	6,432	6,854
Segment gross margin	9,333	9,350	19,394	20,363
Terminals [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Segment assets:	83,766		83,766		71,180
Segment information
Total revenue	4,336	3,898	8,601	7,512
Terminals reporting segment [Member]
Segment information
Revenue	4,336	3,898	8,601	7,512
Gain (loss) on commodity derivatives, net	0	0	0	0
Purchases of natural gas, NGLs and condensate	0	0	0	0
Direct operating expenses	1,584	1,562	3,179	3,237
Segment gross margin	2,752	$ 2,336	5,422	$ 4,275
Other Segments [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Segment assets:	$ 40,231		$ 40,231		$ 26,302

Reporting Segments (Details Tex

Reporting Segments (Details Textual)	6 Months Ended
	Jun. 30, 2015segment
Segment Reporting [Abstract]
Number of Operating Segments	3

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions		Jul. 23, 2015	Jul. 31, 2015	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
General Partners' Capital Account, Units Issued				411,000		411,000		392,000
Distribution declared per common unit (a)	[1]			$ 0.4725	$ 0.4625	$ 0.9450	$ 0.9150
Subsequent Event [Member]
Business Acquisition [Line Items]
Unitholder contributions			$ 0.4
General Partners' Capital Account, Units Issued			21,975
Distribution declared per common unit (a)		$ 0.4725
Distribution Made to Limited Partner, Distributions Declared, Per Unit, Annualized Basis		$ 1.89
[1]	Distributions declared and paid during the three and six months ended June 30, 2015 and 2014 related to prior periods' earnings.