Third Coast Midstream (AMID) 10-Q 15 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	Apr. 30, 2018
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	Mar. 31, 2018
Amendment Flag	false
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding (in shares)		52,858,782
Series A [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		11,009,729
Series C [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		9,241,642

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets
Cash and cash equivalents	$ 8,191	$ 8,782
Restricted cash	18,269	20,352
Accounts receivable, net of allowance for doubtful accounts of $312 and $225 as of March 31, 2018 and December 31, 2017, respectively	87,418	98,132
Inventory	4,795	2,966
Other current assets	25,265	23,420
Assets held for sale	129,247	0
Total current assets	273,185	153,652
Property, plant and equipment, net	1,080,897	1,095,585
Goodwill	67,985	128,866
Restricted cash-long term	5,048	5,045
Intangible assets, net	141,627	174,010
Investments in unconsolidated affiliates	339,271	348,434
Other assets, net	25,249	17,874
Total assets	1,933,262	1,923,466
Current liabilities
Accounts payable	52,685	41,102
Accrued gas and crude oil purchases	14,925	19,986
Accrued expenses and other current liabilities	88,123	68,854
Current portion of long-term debt	5,058	7,551
Liabilities held for sale	3,337	0
Total current liabilities	164,128	137,493
Asset retirement obligations	66,894	66,194
Other long-term liabilities	15,542	2,080
Revolving credit facility	1,214,846	1,201,456
Deferred tax liability	8,274	8,123
Total liabilities	1,469,684	1,415,346
Commitments and contingencies (Note 18)
Convertible preferred units	317,180	317,180
Equity and partners’ capital
General Partner interests (960 thousand and 965 thousand units issued and outstanding as of March 31, 2018 and December 31, 2017, respectively)	(88,746)	(96,552)
Limited Partner interests (52,853 thousand and 52,711 thousand units issued and outstanding as of March 31, 2018 and December 31, 2017, respectively)	221,346	273,703
Accumulated other comprehensive income	12	28
Total partners’ capital	132,612	177,179
Noncontrolling interests	13,786	13,761
Total equity and partners’ capital	146,398	190,940
Total liabilities, equity and partners’ capital	1,933,262	1,923,466
3.77% Senior secured notes (Non-recourse)
Current liabilities
Senior notes	54,682	55,198
8.50% Senior unsecured notes
Current liabilities
Senior notes		418,421
3.97% Trans-Union Secured Senior notes
Current liabilities
Senior notes	29,486	29,937
Credit Agreement [Member]
Current liabilities
Revolving credit facility	$ 712,600	$ 697,900

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Allowance for doubtful accounts receivable	$ 312	$ 225
General partner interest units, outstanding (in shares)	965	965
Preferred, units, outstanding (in shares)	52,853	52,711
Partnership Interest [Member]
General partner interest, units issued (in shares)	960	965
General partner interest units, outstanding (in shares)	960	965
Preferred, units, issued (in shares)	52,853	52,711
Preferred, units, outstanding (in shares)	52,853	52,711
3.77% Senior secured notes (Non-recourse) | Senior Notes
Debt instrument, stated interest rate (percent)	3.77%	3.77%
8.50% Senior unsecured notes | Senior Notes
Debt instrument, stated interest rate (percent)	8.50%	8.50%
3.97% Trans-Union Secured Senior notes | Senior Notes
Debt instrument, stated interest rate (percent)	3.97%	3.97%

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue:
Commodity sales	$ 158,863	$ 123,521
Services	46,906	40,192
Gain on commodity derivatives, net	60	365
Total revenue	205,829	164,078
Operating expenses:
Costs of sales	150,166	115,468
Direct operating expenses	23,446	17,405
Corporate expenses	22,692	30,113
Depreciation, amortization and accretion	21,997	25,570
Gain on sale of assets, net	(95)	(21)
Total operating expenses	218,206	188,535
Operating loss	(12,377)	(24,457)
Other income (expense), net
Interest expense, net of capitalized interest	(13,876)	(17,956)
Other income (expense), net	22	(37)
Earnings in unconsolidated affiliates	12,673	15,402
Loss from continuing operations before income taxes	(13,558)	(27,048)
Income tax expense	(280)	(1,123)
Loss from continuing operations	(13,838)	(28,171)
Loss from discontinued operations	0	(710)
Net loss	(13,838)	(28,881)
Less: Net income attributable to noncontrolling interests	45	1,303
Net loss attributable to the Partnership	(13,883)	(30,184)
General Partner’s interest in net loss	(181)	(420)
Limited Partners’ interest in net loss	$ (13,702)	$ (29,764)
Distribution declared per common unit (in usd per share)	$ 0.4125	$ 0.4125
Limited Partners’ net income (loss) per common unit, basic and diluted:
Income (loss) from continuing operations (in usd per share)	(0.42)	(0.74)
Income (loss) from discontinued operations (in usd per share)	0	(0.01)
Net income (loss) (in usd per share)	$ (0.42)	$ (0.75)
Weighted average number of common units outstanding:
Weighted average number of common units outstanding: basic and diluted (shares)	52,769	51,451

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (13,838)	$ (28,881)
Unrealized gain (loss) related to postretirement benefit plan	(16)	18
Comprehensive loss	(13,854)	(28,863)
Less: Comprehensive income attributable to noncontrolling interests	45	1,303
Comprehensive loss attributable to the Partnership	$ (13,899)	$ (30,166)

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Changes in Partners' Capital and Noncontrolling Interests (Unaudited) - USD ($) $ in Thousands	Total	Panther Asset Management LLC (Panther)	Parent [Member]	Parent [Member]Panther Asset Management LLC (Panther)	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]	General Partner	General PartnerPanther Asset Management LLC (Panther)	Limited Partner [Member]
Partners' Capital at Dec. 31, 2016	$ 585,157		$ 568,402		$ (40)	$ 16,755	$ (47,645)		$ 616,087
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income (loss)	(28,881)		(30,184)			1,303	(420)		(29,764)
Issuance of common units, net of offering costs	(72)		(72)						(72)
Contributions	4,123		4,123				123		4,000
Distributions	(33,967)		(33,967)				(282)		(33,685)
Distributions to NCI owners	(868)					(868)
Contributions from NCI owners	280					280
LTIP vesting							(2,135)		2,135
Tax netting repurchase	(971)		(971)						(971)
Equity compensation expense	4,037		4,037				3,304		733
Other comprehensive income	18		18		18
Partners' Capital at Mar. 31, 2017	528,856		511,386		(22)	17,470	(47,055)		558,463
Partners' Capital at Dec. 31, 2017	190,940		177,179		28	13,761	(96,552)		273,703
Cumulative effect of accounting change (Note 3) at Dec. 31, 2017	(10,691)		(10,691)				(139)		(10,552)
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income (loss)	(13,838)		(13,883)			45	(181)		(13,702)
Contributions	9,870		9,870				9,870		0
Distributions	(30,120)		(30,120)				(392)		(29,728)
Distributions to NCI owners	(20)					(20)
Distribution for acquisition of Trans-Union		$ (38)		$ (38)				$ 38
LTIP vesting							(2,328)		2,328
Tax netting repurchase	(703)		(703)						(703)
Equity compensation expense	1,014		1,014				1,014
Other comprehensive income	(16)		(16)		(16)
Partners' Capital at Mar. 31, 2018	$ 146,398		$ 132,612		$ 12	$ 13,786	$ (88,746)		$ 221,346

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net loss	$ (13,838)	$ (28,881)
Adjustments to reconcile net loss to net cash provided by operating activities including discontinued operations:
Depreciation, amortization and accretion	21,997	29,351
Amortization of deferred financing costs	1,316	1,253
Amortization of weather derivative premium	278	257
Unrealized (gain) loss on derivatives contracts, net	(5,112)	1,273
Non-cash compensation expense	1,014	4,037
(Gain) loss on sale of assets and business, net of transaction costs of $2.5 million (Note 4)	(95)	(228)
Corporate overhead support	0	4,000
Other non-cash items	(15)	1,965
Earnings in unconsolidated affiliates	(12,673)	(15,402)
Distributions from unconsolidated affiliates	12,673	15,402
Deferred tax expense	151	678
Bad debt expense	87	830
Changes in operating assets and liabilities, net of effects of acquisitions:
Accounts receivable	7,251	266
Inventory	(3,399)	(2,626)
Other current assets	(4,174)	3,114
Other assets, net	0	168
Accounts payable	11,200	(9,716)
Accrued gas and crude oil purchases	(4,431)	2,403
Accrued expenses and other current liabilities	2,623	994
Asset retirement obligations	(6)	(41)
Other liabilities	0	(250)
Net cash provided by operating activities	14,847	8,847
Cash flows from investing activities
Contributions to unconsolidated affiliates	(987)	0
Additions to property, plant and equipment and other	(25,946)	(20,221)
Proceeds from disposals of property, plant and equipment	8	51
Insurance proceeds from involuntary conversion of property, plant and equipment	0	150
Distributions from unconsolidated affiliates, return of capital	11,181	7,092
Net cash used in investing activities	(15,744)	(12,928)
Cash flows from financing activities
Proceeds from issuance of common units to public, net of offering costs	0	(72)
Contributions	9,870	123
Distributions	(22,035)	(32,198)
Contribution from noncontrolling interest owners	0	280
Distributions to noncontrolling interests owners	(20)	(868)
LTIP tax netting unit repurchase	(703)	(971)
Payment of deferred financing costs	(1,085)	(1,402)
Payments of other debt	(1,893)	(2,363)
Payments of credit agreement	(119,700)	(325,908)
Borrowings on credit agreement	134,400	82,500
Other	338	(20)
Net cash used in financing activities	(1,774)	(280,899)
Net decrease in cash, cash equivalents, and restricted cash	(2,671)	(284,980)
Cash, Cash equivalents and Restricted cash
Beginning of period	34,179	329,230
Cash and cash equivalents, beginning of period	8,191	16,919
Restricted cash, beginning of period	25,397	323,564
Cash and cash equivalents, end of period	8,191	16,919
Restricted cash, end of period	23,317	27,331
End of period	31,508	44,250
3.77% Senior secured notes (Non-recourse) | Senior Notes
Cash flows from financing activities
Payment of Senior Notes	(507)	0
Cash, Cash equivalents and Restricted cash
Restricted cash, end of period	15,200
3.97% Trans-Union Secured Senior notes | Senior Notes
Cash flows from financing activities
Payment of Senior Notes	$ (439)	$ 0

Condensed Consolidated Stateme8

Condensed Consolidated Statements of Cash Flows (Unaudited) (Parentheticals) - Senior Notes	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2016	May 10, 2016
3.77% Senior secured notes (Non-recourse)
Debt instrument, stated interest rate (percent)	3.77%	3.77%	3.77%
3.97% Trans-Union Secured Senior notes
Debt instrument, stated interest rate (percent)	3.97%	3.97%		3.97%

Organization and Basis of Prese

Organization and Basis of Presentation	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	(1) Organization and Basis of Presentation Organization American Midstream Partners, LP (together with its consolidated subsidiaries, the “Partnership”, “we”, “us”, or “our”) is a growth-oriented Delaware limited partnership that was formed in August 2009 to own, operate, develop and acquire a diversified portfolio of midstream energy assets. The Partnership’s general partner, American Midstream GP, LLC (the “General Partner”), is 77% directly owned by High Point Infrastructure Partners, LLC (“HPIP”) and 23% indirectly owned by Magnolia Infrastructure Holdings, LLC (“Magnolia”), both of which are affiliates of ArcLight Capital Partners, LLC ("ArcLight"). Our capital accounts consist of notional General Partner units and units representing limited partner interests. We provide critical midstream infrastructure that links producers of natural gas, crude oil, NGLs, condensate and specialty chemicals to numerous intermediate and end-use markets. Through our five reportable segments, (1) gas gathering and processing services, (2) liquid pipelines and services, (3) natural gas transportation services, (4) offshore pipelines and services, and (5) terminalling services, we engage in the business of gathering, treating, processing and transporting natural gas; gathering, transporting, storing, treating and fractionating NGLs; gathering, storing and transporting crude oil and condensates and storing specialty chemical products and refined products. Most of our cash flow is generated from fee-based and fixed-margin compensation for gathering, processing, transporting and treating natural gas and crude oil, firm capacity reservation charges, interruptible transportation charges, guaranteed firm storage contracts, throughput fees and other optional charges associated with ancillary services. Our primary assets are strategically located in some of the most prolific onshore and offshore producing regions and key demand markets in the United States. Our gathering and processing assets are primarily located in (i) the Permian Basin of West Texas, (ii) the Cotton Valley/Haynesville Shale of East Texas, (iii) the Eagle Ford Shale of South Texas, (iv) the Bakken Shale of North Dakota, and (v) offshore in the Gulf of Mexico. Our transmission and terminal assets are in key demand markets in Oklahoma, Alabama, Arkansas, Louisiana, Mississippi and Tennessee and in the Port of New Orleans in Louisiana and the Port of Brunswick in Georgia. Basis of presentation The accompanying condensed consolidated financial statements have been prepared in accordance with GAAP for interim consolidated financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. They do not include all of the information and notes required by GAAP for annual consolidated financial statements and should therefore be read in conjunction with our annual consolidated financial statements and notes presented in our Annual Report on Form 10-K for the year ended December 31, 2017. In the opinion of management, the condensed consolidated financial statements contain all adjustments, consisting only of normal recurring adjustments, necessary to fairly state our financial position, results of operations and cash flows for the interim periods reported. These condensed consolidated financial statements follow the same significant accounting policies as those included in our annual consolidated financial statements for the year ended December 31, 2017, except for the adoption of new standards. See Notes 2 and 3 for additional information on the adoption of new standards. Certain prior period amounts have been reclassified to conform to the current presentation. The accompanying condensed consolidated financial statements include accounts of the Partnership and its consolidated subsidiaries. All significant inter-company accounts and transactions have been eliminated in the preparation of the accompanying condensed consolidated financial statements. We may enter into transactions with ArcLight or its affiliates whereby we receive midstream assets or other businesses in exchange for cash or Partnership's equity. As the transactions are between entities under common control we account for the net assets acquired at the affiliate's historical cost basis, whether the transactions are considered assets or business acquisitions. In certain cases, our historical financial statements will be revised to include the results attributable to the assets acquired from the later of April 15, 2013 (the date ArcLight affiliates obtained control of our General Partner) or the date the ArcLight affiliates obtained control of the assets or business acquired.

New Accounting Pronouncements

New Accounting Pronouncements	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
New Accounting Pronouncements	(2) New Accounting Pronouncements Adopted in 2018 The Partnership adopted Accounting Standards Update (“ASU”) No. 2014-09, “ Revenue from Contracts with Customers (Topic 606) ” issued by the Financial Accounting Standards Board (FASB) on January 1, 2018. See Note 3 - Revenue Recognition for more information on the impact of its adoption . In August 2016, the FASB issued ASU No. 2016-15, “ Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments ” (“ASU 2016-15”). ASU 2016-15 provides specific guidance on eight cash flow classification issues, including debt prepayment or debt extinguishment costs, to reduce diversity in practice. ASU 2016-15 is effective for interim and annual periods beginning after December 15, 2017. There was no impact of the retrospective adoption of this ASU on the Partnership’s condensed consolidated statement of cash flows. In November 2016, the FASB issued ASU No. 2016-18 (“ASU 2016-18”), “ Statement of Cash Flows (Topic 230): Restricted Cash ”, which requires amounts described as restricted cash and restricted cash equivalents to be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. A reconciliation between the balance sheet and the statement of cash flows must be disclosed when the balance sheet includes more than one line item for cash, cash equivalents, restricted cash and restricted cash equivalents. ASU 2016-18 is effective for fiscal years beginning after December 15, 2017. We adopted both ASU 2016-15 and ASU 2016-18 on its effective date of January 1, 2018 using the retrospective transition method. Upon adoption of the standards, the Partnership’s condensed consolidated statement of cash flows for the period ended March 31, 2017 was impacted as follows (in thousands): Three months ended March 31, 2017 Condensed Consolidated Statement of Cash Flows As Previously Reported Effect of Adoption As Adjusted Cash flows from operating activities Net loss $ (28,881 ) $ — $ (28,881 ) Adjustments to reconcile net loss to net cash provided by operating activities including discontinued operations (excluding ‘Other non-cash items’) 39,416 — 39,416 Restricted cash, short-term (3,135 ) 3,135 (1 ) — Changes in operating assets and liabilities, net of effects of assets acquired and liabilities assumed (excluding ‘Restricted cash’) (1,633 ) (55 ) (1 ) (1,688 ) Net cash provided by (used in) operating activities 5,767 3,080 8,847 Cash flows from investing activities Restricted cash 299,313 (299,313 ) (1 ) — Other investing activities (excluding ‘Restricted cash’) (12,928 ) (12,928 ) Net cash provided by (used in) investing activities 286,385 (299,313 ) (12,928 ) Cash flows from financing activities Other financing activities (280,899 ) — (280,899 ) Net cash used in financing activities (280,899 ) — (280,899 ) Net increase (decrease) in cash, cash equivalents, and restricted cash 11,253 (296,233 ) (284,980 ) Cash, cash equivalents and Restricted Cash Beginning of period 5,666 323,564 329,230 End of period $ 16,919 $ 27,331 $ 44,250 _____________________________________________ (1) ASU 2016-18 adjustment to move restricted cash to be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the condensed consolidated statement of cash flows. In May 2017, the FASB issued ASU No. 2017-09, “ Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting ” (“ASU 2017-09”). ASU 2017-09 was issued with the intent to clarify the scope of modification accounting and when it should be applied to a change to the terms or conditions of a share-based payment award. Under the new guidance, modification accounting is required for all changes to share based payment awards, unless all the following conditions are met: (i) there is no change to the fair value of the award, (ii) the vesting conditions have not changed, and iii) the classification of the award as an equity instrument or a debt instrument has not changed. The accounting update was adopted on its effective date January 1, 2018, on a prospective basis. Based on historical patterns of our unit-based awards, which did not involve material modifications, we do not expect the adoption of this accounting update to have a material impact on our consolidated financial position, cash flows or results of operations. In March 2018, the FASB issued ASU No. 2018-05, “ Income Taxes (Topic 740): Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118 (SEC Update) ”, to provide guidance for companies that have not completed their accounting for the income tax effects of the Tax Cuts and Jobs Act (the “Act”) in the period of enactment. The measurement period begins in the reporting period that includes the Act’s enactment date of December 22, 2017, and ends when a company has obtained, prepared and analyzed the information needed to complete the accounting requirements under ASU No. 2018-05/Topic 740 and should not extend beyond one year from the enactment date. The impact of adopting the new guidance on our consolidated financial position, cash flows or results of operations, as well as on related disclosures was immaterial. Standards Not Yet Adopted In February 2016, the FASB issued ASU No. 2016-02 (Topic 842) " Leases ", which supersedes the lease recognition requirements in Accounting Standards Codification (“ASC”) Topic 840, "Leases" . Under ASU No. 2016-02, lessees are required to recognize assets and liabilities on the balance sheet for most leases and to provide enhanced disclosures. Leases will continue to be classified as either finance or operating. ASU No. 2016-02 is effective for annual reporting periods, and interim periods within those years beginning after December 15, 2018. Entities are required to use a modified retrospective approach for leases that exist or are entered into after the beginning of the earliest comparative period in the financial statements, and there are certain optional practical expedients that an entity may elect to apply. Full retrospective application is prohibited, and early adoption by public entities is permitted. We are in the process of evaluating the impact of ASU No. 2016-02 on our consolidated financial statements as we will be required to reflect our various lease obligations and associated asset use rights on our consolidated balance sheets. The adoption may also impact our debt covenant compliance and may require us to modify or replace certain of our existing information systems. We are finalizing our selection of a third-party consulting firm to assist us with the adoption of the new guidance and are currently in the Impact Assessment phase. We are not yet able to determine whether the adoption of this standard will have a material impact on our consolidated financial statements and related disclosures, including additional changes, if any, to our accounting system to capture data for disclosure purposes. We will adopt the guidance on its effective date January 1, 2019. In January 2018, the FASB issued ASU No. 2018-01, “ Leases - Land Easement Practical Expedient for Transition to Topic 842 ” to provide an optional transition practical expedient to forego evaluation under Topic 842 of existing or expired land easements that were not previously accounted for as leases under the current guidance found in Topic 840. An entity that elects this practical expedient should evaluate new or modified land easements under Topic 842 beginning at the date that the entity adopts Topic 842. An entity that does not elect this practical expedient should evaluate all existing or expired land easements in connection with the adoption of the new lease requirements in Topic 842 to assess whether they meet the definition of a lease. As discussed above, we are finalizing our selection of a third-party consulting firm to assist us with the adoption of the new guidance and are currently in the Impact Assessment phase. We are not yet able to determine whether we would elect this practical expedient or whether the adoption of this standard will have a material impact on our consolidated financial position, results of operations and cash flows, as well as related disclosures, including additional changes, if any, to our accounting system to capture data for disclosure purposes. We will adopt this on its effective date January 1, 2019. In June 2016, the FASB issued ASU 2016-13, “ Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” . This guidance will become effective for interim and annual periods beginning after December 15, 2019. We expect to adopt this ASU on January 1, 2020, and we are currently evaluating the effect that adopting this guidance will have on our consolidated financial position, results of operations and cash flows.

Revenue Recognition

Revenue Recognition	3 Months Ended
	Mar. 31, 2018
Revenue from Contract with Customer [Abstract]
Revenue Recognition	(3) Revenue Recognition Adoption of Topic 606 ASU No. 2014-09, “ Revenue from Contracts with Customers (Topic 606)”, supersedes previous revenue recognition guidance, establishes a principle-based model to be applied to all contracts with customers and introduces enhanced disclosure requirements. It also requires the use of more estimates and judgments than the previous standards. We adopted the new standard and the series of related accounting standard updates that followed (collectively referred to as “Topic 606”) on January 1, 2018, using the modified retrospective method applied to those contracts which were not completed as of January 1, 2018 and any new contracts entered into after January 1, 2018. Under this method, the financial information of previous years has not been adjusted. While the Partnership does not expect future net earnings to be materially impacted by revenue recognition timing changes, we recognized the cumulative effect of the adoption as a decrease in the opening balance of partners' capital of approximately $10.7 million . The adjustment was primarily related to four contracts where the allocation of the transaction prices resulted in changes to the pattern and timing of revenue recognition for those contracts as compared to the cash received for certain up-front fees for capital recovery as well as contracts with tiered fee structures. The following tables summarize the impacts of adopting Topic 606 on the Partnership’s condensed consolidated financial statements as of and for the three months ended March 31, 2018, adjusting for the differences between revenue as reported following adoption of Topic 606 and revenue as it would have been reported under previous standards (in thousands): Three months ended March 31, 2018 Condensed Consolidated Statement of Income As Reported Adjustments Amounts without Adoption of Topic 606 Revenue Commodity sales $ 158,863 $ 5,242 $ 164,105 Services 46,906 (2,681 ) 44,225 Operating expenses Costs of sales 150,166 3,165 153,331 Direct operating expenses 23,446 (456 ) 22,990 Operating loss (12,377 ) (148 ) (12,525 ) Net loss attributable to the Partnership $ (13,883 ) $ (148 ) $ (14,031 ) General Partner’s interest in net loss $ (181 ) $ (2 ) $ (183 ) Limited Partners’ interest in net loss (13,702 ) (146 ) (13,848 ) As of March 31, 2018 Condensed Consolidated Balance Sheet (in thousands) As Reported Adjustments Amounts without Adoption of Topic 606 Assets Accounts receivable, net $ 87,418 $ (67,553 ) $ 19,865 Unbilled revenue — 67,553 67,553 Other current assets 25,265 — 25,265 Other noncurrent assets 25,249 (3,419 ) 21,830 Liabilities Accrued expenses and other current liabilities 88,123 — 88,123 Liabilities held for sale 3,337 (459 ) 2,878 Other noncurrent liabilities 15,542 (13,503 ) 2,039 Equity and partners’ capital General partner interests $ (88,746 ) $ 137 $ (88,609 ) Limited partner interests 221,346 10,406 231,752 The majority of the adjustments in the table above were associated with our natural gas gathering, processing and transportation revenues and our terminalling and storage revenues. The magnitude of the future effect of implementing Topic 606 is dependent on future customer volumes, subject to the impacted contracts and commodity prices for those volumes. While reported revenues and expenses can be materially reduced, these presentation changes may not materially impact net earnings. Revenue from Contracts with Customers Our revenue is derived from the provision of gathering, processing, transportation, terminalling and storage services and the sale of commodities primarily to marketers and brokers, refiners and chemical manufacturers, utilities and power generation customers, industrial users, and local distribution companies. Beginning on January 1, 2018, we account for revenue from contracts with customers in accordance with Topic 606. The unit of account in Topic 606 is a performance obligation, which is a promise in a contract to transfer to a customer either a distinct good or service (or bundle of goods or services) or a series of distinct goods or services provided over a period of time. Topic 606 requires that a contract’s transaction price, which is the amount of consideration to which an entity expects to be entitled in exchange for transferring promised goods or services to a customer, is to be allocated to each performance obligation in the contract based on relative standalone selling prices and recognized as revenue when (point in time) or as (over time) the performance obligation is satisfied. Under Topic 606, we disaggregate our revenues for disclosure purposes by segment and type of activity. These categories depict how the nature, amount, timing and uncertainty of revenues and cash flows are affected by economic factors. Our business activities are conducted through our five reportable segments, shown below. See Note 21 - Reportable Segments for further discussion of our reportable segments. The following table presents our segment revenues from contracts with customers disaggregated by type of activity (in thousands): Three months ended March 31, 2018 Gas Gathering and Processing Services Liquid Pipelines and Services Natural Gas Transportation Services Offshore Pipelines and Services Terminalling Services Total Commodity sales: Natural gas $ 1,906 $ — $ 6,637 $ 2,437 $ — $ 10,980 NGLs 21,150 — — 38 — 21,188 Condensate 5,648 — — 34 — 5,682 Crude oil — 115,782 — — — 115,782 Other sales (1) 183 — 4 40 5,004 5,231 Services: Gathering and processing 6,250 — — 866 — 7,116 Transportation 105 3,588 9,412 8,661 — 21,766 Terminalling and storage — — — — 11,833 11,833 Other services (2) 434 403 10 4,783 561 6,191 Revenues from contracts with customers $ 35,676 $ 119,773 $ 16,063 $ 16,859 $ 17,398 $ 205,769 (1) Other commodity sales for our Terminalling Services segment include sales of refined product. The Partnership is actively marketing for sale all of its assets in the Terminalling Services segment. See Note 4 - Acquisitions and Dispositions. (2) Other services in our Offshore Pipelines and Services segment include asset management services. Commodity Sales The Partnership sells various commodities as shown in the table above. Generally, for the majority of our commodity sales contracts: (i) each unit of product is a separate performance obligation, since our promise is to sell multiple distinct units of product at a point in time; (ii) the transaction price principally consists of variable consideration, which is determinable on commodity index prices for the volume of the product sold to the customer that month; and (iii) the transaction price is allocated to each performance obligation based on the product’s standalone selling price. Revenues from sales of commodities are recognized at the point in time when control of the commodity transfers to the customer, which generally occurs upon delivery of the product to the customer or its designee. Payment is generally received from the customer in the month following delivery. Contracts with customers have varying terms, including spot sales, month-to-month contracts and multi-year agreements. In our Liquid Pipelines and Services segment, we enter into purchase and sales contracts as well as buy/sell contracts with counterparties, under which contracts we gather and transport different types of crude oil and eventually sell the crude oil to either the same counterparty or different counterparties. For each of these arrangements, the Partnership assesses if control of the underlying commodity volumes transfer to the Partnership. Generally, the Partnership is unable to direct the use of the commodity volumes it purchases from the supplier because the Partnership is contractually required to redeliver an equivalent volume of the commodity back to the supplier or to a specified customer. Occasionally, we enter into crude oil inventory exchange arrangements with the same counterparty where the purchase and sale of inventory are considered in contemplation of each other. These types of arrangements are accounted for as inventory exchanges and are recorded on a net basis. Services The Partnership provides gathering, processing, transportation, terminalling and storage services pursuant to a variety of contracts. Generally, for the majority of these contracts: (i) our promise is to transfer (or stand ready to transfer) a series of distinct integrated services over a period of time, which is a single performance obligation and (ii) the transaction price includes fixed or variable consideration, or both fixed and variable consideration. The amount of consideration is determinable at contract inception or at each month end based on our right to invoice at month end for the value of services provided to the customer that month. The transaction price is recognized as revenue over the service period specified in the contract as the services are rendered using a time-based (passage of time) or units-based (units of service transferred) method for measuring provision of the services. Progress towards satisfying our performance obligation is based on the firm or interruptible nature of the promised service and the terms and conditions of the contract (such as contracts with or without makeup rights). Payment is generally received from the customer in the month of service or the month following the service. Contracts with customers generally are a combination of month-to-month and multi-year agreements. Firm Services Firm services are services that are promised to be available to the customer at all times during the term of the contract, with limited exceptions. These agreements require customers to deliver, transport or throughput a minimum volume over an agreed upon period and substantially all of such agreements are entered into with customers to economically support the return on our capital expenditure necessary to construct the related asset. Our firm service contracts are typically structured with take-or-pay or minimum volume provisions, which specify minimum service quantities a customer will pay for even if it chooses not to receive or use them in the specified service period (referred to as “deficiency quantities”). Under firm service contracts, we record a receivable from the customer in the period that services are provided or when the transaction occurs, including amounts for deficiency quantities from customers associated with minimum volume commitments. If a customer has a make-up right associated with a deficiency, we defer the revenue attributable to the counterparty’s make-up right and subsequently recognize the revenue at the earlier of when the deficiency volume is delivered or shipped, when the make-up right expires or when it is determined that the customer’s ability to utilize the make-up right is remote. At March 31, 2018, customer deficiencies associated with firm services were immaterial. Interruptible Services Interruptible services are the opposite of firm services in that such services are provided to the extent that we have available capacity. Generally, we do not have an obligation to perform these services until we accept a customer’s periodic request for service. For the majority of these contracts, the customer will pay only for the actual quantities of services it chooses to receive or use, and we typically recognize the transaction price as revenue as those units of service are transferred to the customer in the specified service period. Gathering and Processing In our Gas Gathering and Processing Services segment, we purchase gas volumes from producers at the wellhead, production facility, or at receipt points on our systems typically at an index price, and charge the producer fees associated with the downstream gathering and processing services. Services can be firm if subject to a minimum volume commitment or acreage dedication or interruptible when offered on an as requested, non-guaranteed basis. Revenue for fee-based gathering and processing services are valued based on the rate in effect for the month of service and is recognized in the month of service based on the volumes of natural gas we gather, process and fractionate. Under these arrangements, we may take control of: (i) none of the commodities we sell (i.e., residue gas or NGLs), (ii) a portion of the commodities we sell, or (iii) all of the commodities we sell. In those instances where we purchase and obtain control of the entire natural gas stream in our producer arrangements, we have determined these are contracts with suppliers rather than contracts with customers and therefore, these arrangements are not included in the scope of Topic 606. These supplier arrangements are subject to updated guidance in ASC 705, “ Cost of Sales and Services ,” whereby any embedded fees within such contracts, which historically have been reported as services revenue, are now reported as a reduction to cost of sales upon adoption of Topic 606. In those instances where we remit all of the cash proceeds received from third parties for selling the extracted commodities to the producer, less the fees attributable to these arrangements, we have determined that the producer has control over these commodities. Upon adoption of Topic 606, we eliminated recording both sales revenue (natural gas and products) and cost of sales amounts and now only record fees attributable to these arrangements as service revenues. In other instances where we do not obtain control of the extracted commodities we sell, we are acting as an agent for the producer and, upon adoption of Topic 606, we have continued to recognize services revenue for the net amount of consideration we retain in exchange for our service. The Partnership may charge additional service fees to customers for a portion of the contract term (i.e., for the first year of a contract or until reaching a volume threshold) due to the significant upfront capital investment, and these fees are initially deferred and recognized to revenue over the expected period of customer benefit, generally the lesser of the expected contract term or the life of the related properties. Transportation Our transportation operations generally consist of fee-based activities associated with transporting crude oil, natural gas, and NGL on pipelines, gathering systems and trucks. Revenues from pipeline tariffs and fees are associated with the transportation at a published tariff, as well as revenues associated with agreements for committed capacity on various assets. We primarily recognize pipeline tariff and fee revenues over time based on the volumes delivered and invoiced. The majority of our pipeline tariff and fee revenues are based on actual volumes and rates. As is common in the pipeline transportation industry, our tariffs incorporate a loss allowance factor. The intent of the allowance in arrangements for the transportation of natural gas is to approximate the natural shrink that occurs when transporting the gas. For crude oil transportation arrangements, loss allowance provisions are immaterial to the Partnership. In the event the Partnership retains excess natural gas and crude oil and subsequently sells the commodity to a third party, the sale is recorded at that point in time as a commodity sale. Terminalling and Storage In our Terminalling Services segment, we generally receive fee-based compensation on guaranteed firm storage contracts, throughput fees charged to our customers when their products are either received or disbursed, and other operational charges associated with ancillary services provided to our customers, such as excess throughput, steam heating and truck weighing at our marine terminals. Storage fees resulting from short-term and long-term contracts are typically recognized in revenue ratably over the term of the contract regardless of the actual storage capacity utilized. Other Items in Revenue The following table presents the reconciliation of our revenues from contracts with customers to segment revenues and total revenues as disclosed in our condensed consolidated statement of operations (in thousands): Three months ended March 31, 2018 Gas Gathering and Processing Services Liquid Pipelines and Services Natural Gas Transportation Services Offshore Pipelines and Services Terminalling Services Total Revenues from contracts with customers $ 35,676 $ 119,773 $ 16,063 $ 16,859 $ 17,398 $ 205,769 Gains (losses) on commodity derivatives, net 2 58 — — — 60 Total revenues of reportable segments $ 35,678 $ 119,831 $ 16,063 $ 16,859 $ 17,398 $ 205,829 We may utilize derivatives in connection with contracts with customers. We purchase and take title to a portion of the NGLs and crude oil that we sell, which may expose us to changes in the price of these products in our sales markets. We do not take title to the natural gas we transport and therefore have no direct commodity price exposure to natural gas. Derivative revenue is not included as a component of revenue from contracts with customers, but is included in other items in revenue. Contract Balances Our contract balances primarily consist of customer receivables and contract assets and liabilities. Trade accounts receivable, net consists of the following as presented on our condensed consolidated balance sheet (in thousands): March 31, 2018 Receivables arising from revenue contracts Unbilled customer receivables $ 67,553 Billed customer receivables 20,177 Allowance for doubtful accounts (312 ) Accounts receivable, net $ 87,418 Our contract assets and liabilities primarily relate to contracts where allocations of the transaction prices result in differences to the pattern and timing of revenue recognition as compared to contractual billings. Where payments are received in advance of recognition as revenue, contract liabilities are created. Where we have earned revenue and our right to invoice the customer is conditioned on something other than the passage of time, contract assets are created. The following table presents the change in the contract assets and liability balances during the three months ended March 31, 2018 (in thousands): Contract Assets Contract Liabilities Balance at December 31, 2017 $ — $ 2,136 Topic 606 implementation 2,555 13,246 Amounts recognized as revenue — (502 ) Additions 864 1,205 Total balance at March 31, 2018 3,419 16,085 Classified as held for sale — (708 ) Balance at March 31, 2018 $ 3,419 $ 15,377 Current — 998 Noncurrent 3,419 14,379 Balance at March 31, 2018 $ 3,419 $ 15,377 In our condensed consolidated balance sheet as of March 31, 2018, current portions of contract assets are included in other current assets, noncurrent portions of contract assets are included in other (noncurrent) assets, current portions of contract liabilities are included in other current liabilities and noncurrent portions of contract liabilities are included in other long-term liabilities. Remaining Performance Obligations The Partnership applies the practical expedients in Topic 606 and does not disclose consideration for remaining performance obligations with an original expected duration of one year or less or for variable consideration related to unsatisfied (or partially unsatisfied) performance obligations. Therefore, the following table as of March 31, 2018, represents only revenue expected to be recognized from contracts where the price and quantity of the product or service are fixed: Remainder of 2018 2019 2020 2021 2022 Thereafter Total Gathering and processing revenues supported by minimum volume commitments $ 9,252 $ 12,743 $ 12,743 $ 12,720 $ 12,467 $ 19,155 $ 79,080 Transportation agreements 15,921 19,233 18,475 18,207 18,100 190,416 280,352 Terminalling and storage throughput agreements 10,821 12,823 6,220 2,715 1,593 — 34,172 Other 1,170 1,560 1,560 — — — 4,290 Total $ 37,164 $ 46,359 $ 38,998 $ 33,642 $ 32,160 $ 209,571 $ 397,894 Due to the application of the practical expedients, the table above represents only a portion of the Partnership’s expected future consolidated revenues and it is not necessarily indicative of the expected trend in total revenues for the Partnership. Certain contracts do not meet the requirements for presentation in the table above due to the term being one year or less and due to variability in the amount of performance obligation remaining, variability in the timing of recognition or variability in consideration. Acreage dedications do require us to perform future services but do not contain a minimum level of services and are therefore excluded from this presentation. Long-term supply and logistics arrangements contain variable timing, volumes and/or consideration and are excluded from this presentation.

Acquisitions and Dispositions

Acquisitions and Dispositions	3 Months Ended
	Mar. 31, 2018
Discontinued Operations and Disposal Groups [Abstract]
Acquisition and Dispositions	(4) Acquisitions and Dispositions Acquisitions As more fully described in our Annual Report for the year ended December 31, 2017, during 2017, the Partnership completed various acquisitions, the results of which are fully reflected in the first quarter of 2018, but are not reflected in the comparable period of 2017 due to the closing dates of the acquisitions. The pro forma effects of these acquisitions were immaterial to our condensed consolidated statement of operations for the three months ended March 31, 2017 and, therefore, have not been separately disclosed. Acquisitions accounted for as business combinations included the following: • On June 2, 2017, we acquired 100% of the Viosca Knoll Gathering System (“VKGS”) from Genesis Energy, L.P. for total consideration of approximately $32 million in cash. • On August 8, 2017, we acquired 100% of the interest in Panther Offshore Gathering Systems, LLC (“POGS”), Panther Pipeline, LLC (“PPL”) and Panther Operating Company, LLC (“POC” and, together with POGS and PPL, “Panther”) from Panther Asset Management LLC for approximately $60.9 million . • On November 3, 2017, we completed the acquisition of 100% of the equity interests in Trans-Union Interstate Pipeline, LP (“Trans-Union”) from affiliates of ArcLight, for a total consideration of approximately $49.4 million . Additionally, we acquired the following interests in 2017 that are accounted for as investments in unconsolidated affiliates: • On August 8, 2017, we entered into a new joint venture agreement with Targa Midstream Services, LLC (“Targa”) by which our previously wholly owned subsidiary Cayenne Pipeline, LLC became the Cayenne joint venture between Targa and us. • On September 29, 2017, we acquired an additional 15.5% equity interest in Class A units of Delta House from affiliates of ArcLight for total cash consideration of approximately $125.4 million . • On October 27, 2017, American Midstream Emerald, LLC, a wholly-owned subsidiary of the Partnership, entered into a purchase and sale agreement with Emerald Midstream, LLC, an ArcLight affiliate, to purchase an additional 17.0% equity interest in Destin for total consideration of $30.0 million . Prior to 2017, we acquired other interests from Emerald, as detailed in Note 10 - Investments in Unconsolidated Affiliates, collectively referred to as the “Emerald Transactions.” During the three months ended March 31, 2018, there were no acquisitions. Planned Dispositions Business Held for Sale During 2017, the Partnership began actively marketing for sale all of its assets in the Terminalling Services segment as part of its plan to divest certain non-core assets and utilize the proceeds to fund future acquisitions and growth projects. On February 16, 2018, the Partnership entered into a definitive agreement for the sale of our refined products terminals (the "Refined Products Business") to DKGP Energy Terminals LLC, a joint venture between Delek Logistics Partners, LP and Green Plains Partners LP, for approximately $138.5 million in cash, subject to working capital adjustments. Accordingly, we have presented the assets and liabilities of the Refined Products Business as held for sale. The Refined Products Business is a portion of the Terminalling Services segment consisting of two terminal facilities located in Caddo Mills, Texas and North Little Rock, Arkansas. As such, this planned disposition does not meet the criteria for discontinued operations. In view of the planned sale, which remains subject to customary closing conditions, we have classified our assets and liabilities of the Refined Products Business in current assets and liabilities held for sale on our condensed consolidated balance sheet. On May 11, 2018, we received notification that the Federal Trade Commission had requested additional information and documentary materials with respect to the planned sale. We and the counterparties to this planned transaction are reviewing this request and will be working to coordinate an appropriate response. Included in the disposal group are the following assets and liabilities (in thousands): March 31, 2018 Accounts receivable, net $ 3,376 Inventory 1,571 Other current assets 893 Property, plant and equipment, net 32,129 Goodwill 61,163 Intangible assets 29,403 Other non-current assets 712 Total assets held for sale $ 129,247 Accounts payable $ 1,219 Accrued gas purchases 630 Accrued expenses and other current liabilities 881 Contract liabilities, long-term 607 Total liabilities held for sale $ 3,337 Net income from continuing operations before income taxes for the Refined Products Business was $2.4 million and $1.8 million for the three months ended March 31, 2018 and 2017, respectively. Discontinued Operations On September 1, 2017, the Partnership completed the disposition of its propane business (the “Propane Business”) pursuant to the Membership Interest Purchase Agreement dated July 21, 2017, between AMID Merger LP, a wholly owned subsidiary of the Partnership, and SHV Energy N.V. Through the transaction, we divested Pinnacle Propane’s 40 service locations; Pinnacle Propane Express’ cylinder exchange business and related logistics assets; and the Alliant Gas utility system. Prior to the sale, we moved the trucking business from the Propane Marketing Services segment to the Liquid Pipelines and Services segment. With the disposition of the Propane Business, we eliminated the Propane Marketing Services segment. In connection with the transaction, the Partnership received approximately $170.0 million in cash, net of customary closing adjustments. We recorded a gain of $47.4 million , net of $2.5 million of transaction costs, which was included in (Gains) losses on sale of assets and business line item on the Partnership's consolidated statement of operations in the period ended September 30, 2017. The Partnership has reported the accounts and the results of our Propane Business as discontinued operations in our condensed consolidated statements of operations for the three months ended March 31, 2017. Summarized financial information related to the Propane Business is set forth in the tables below (in thousands): Three months ended March 31, 2017 Total revenue $ 35,554 Total operating expenses 36,305 Operating loss (751 ) Other income 41 Income tax expense — Loss from discontinued operations before taxes $ (710 ) Partnership’s loss from discontinued operations, net of tax $ (710 ) Depreciation and amortization $ 3,781 Capital expenditures $ 1,119 Operating non-cash items Unrealized gain loss on derivative contracts, net $ 901

Inventory (Notes)

Inventory (Notes)	3 Months Ended
	Mar. 31, 2018
Inventory Disclosure [Abstract]
Inventory	(5) Inventory Inventory consists of the following (in thousands): March 31, 2018 December 31, 2017 Crude oil $ 4,378 $ 1,553 NGLs 282 347 Refined products — 934 Materials, supplies and equipment 135 132 Total inventory $ 4,795 $ 2,966

Other Current Assets

Other Current Assets	3 Months Ended
	Mar. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Current Assets	(6) Other Current Assets Other current assets consist of the following (in thousands): March 31, 2018 December 31, 2017 Prepaid insurance $ 6,341 $ 8,944 Insurance receivables 1,741 1,741 Due from related parties 5,427 4,362 Other receivables 6,393 5,187 Risk management assets 5,363 3,186 Total other current assets $ 25,265 $ 23,420

Risk Management Activities

Risk Management Activities	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Risk Management Activities	(7) Risk Management Activities We are exposed to certain market risks related to the volatility of commodity prices and changes in interest rates. To monitor and manage these market risks, we have established comprehensive risk management policies and procedures. We do not enter into derivative instruments for any purpose other than hedging commodity price risk, interest rate risk, and weather risk. We do not speculate using derivative instruments. Commodity Derivatives To manage the impact of the risks associated with changes in the market price of NGL, crude oil, refined products and natural gas purchases and sales in our day-to-day business, we use a combination of fixed price swap and forward contracts. Our forward contracts that qualify for the Normal Purchase Normal Sale (“NPNS”) exception under GAAP are recognized when the underlying physical transaction is delivered . In accordance with ASC 815, Derivatives and Hedging, if it is determined that a transaction designated as NPNS no longer meets the scope of the exception, the fair value of the related contract is recorded on the balance sheet (as an asset or liability) and the difference between the fair value and the contract amount is immediately recognized through earnings. We measure our commodity derivatives at fair value using the income approach, which discounts the future net cash settlements expected under the derivative contracts to a present value. These valuations utilize indirectly observable (“Level 2”) inputs, including contractual terms and commodity prices observable at commonly quoted intervals. The following table summarizes the net notional volumes of our outstanding commodity-related derivatives, excluding those contracts that qualified for the NPNS exception as of March 31, 2018 and December 31, 2017, none of which were designated as hedges for accounting purposes. March 31, 2018 December 31, 2017 Commodity Swaps Volume Maturity Volume Maturity NGLs Fixed Price (gallons) 1,407,000 January 2019 — — Crude Oil Fixed Price (barrels) 17,000 April 2018 — — Interest Rate Swaps To manage the impact of the interest rate risk associated with our Credit Agreement, as defined in Note 13 - Debt Obligations , we enter into interest rate swaps from time to time, effectively converting a portion of the cash flows related to our long-term variable rate debt into fixed rate cash flows. As of March 31, 2018, and December 31, 2017, we had a combined notional principal amount of $550.0 million respectively of variable-to-fixed interest rate swap agreements. As of March 31, 2018, the maximum length of time over which we have hedged a portion of our exposure due to interest rate risk is through December 31, 2022. The fair value of our interest rate swaps was estimated using a valuation methodology based upon forward interest rates and 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, which represent Level 2 inputs in the valuation hierarchy, are obtained from independent pricing services, and we have made no adjustments to those prices. Weather Derivative In the second quarter of 2017, we entered into a yearly weather derivative arrangement to mitigate the impact of potential unfavorable weather on our operations under which we could receive payments totaling up to $30.0 million in the event that a hurricane of certain strength passes through the areas identified in the derivative agreement. The weather derivative, which is accounted for using the intrinsic value method, was entered into with a single counterparty, and we were not required to post collateral. We paid no premiums during each of the three months ended March 31, 2018 and 2017 . Premiums are amortized to Direct operating expenses on a straight-line basis over the one -year term of the contract. Unamortized amounts associated with the weather derivatives were approximately $0.2 million and $0.5 million as of March 31, 2018 and December 31, 2017 , respectively, and are included in Other current assets on the condensed consolidated balance sheets. The following table summarizes the fair values of our derivative contracts (before netting adjustments) included in the condensed consolidated balance sheets (in thousands): Asset Derivatives Liability Derivatives Type Balance Sheet Classification March 31, December 31, 2017 March 31, December 31, 2017 Commodity derivatives Other current assets $ 5 $ — $ — $ — Commodity derivatives Accrued expenses and other current liabilities — — (64 ) — Interest rate swaps Other current assets $ 5,132 $ 2,678 $ — $ — Interest rate swaps Other assets net 11,524 8,807 — — Weather derivatives Other current assets $ 231 $ 509 $ — $ — Total $ 16,892 $ 11,994 $ (64 ) $ — The following tables present the fair value of our recognized derivative assets and liabilities on a gross basis and amounts offset in the condensed consolidated balance sheets that are subject to enforceable master netting arrangements (in thousands): Gross Risk Management Position Netting Adjustments Net Risk Management Position Balance Sheet Classification March 31, December 31, 2017 March 31, December 31, 2017 March 31, December 31, 2017 Other current assets $ 5,368 $ 3,187 $ (5 ) $ — $ 5,363 $ 3,187 Other (noncurrent) assets, net 11,524 8,807 — — 11,524 8,807 Total assets $ 16,892 $ 11,994 $ (5 ) $ — $ 16,887 $ 11,994 Accrued expenses and other current liabilities $ (64 ) $ — $ 5 $ — $ (59 ) $ — Total liabilities $ (64 ) $ — $ 5 $ — $ (59 ) $ — For each of the three months ended March 31, 2018 and 2017 , the realized and unrealized gains (losses) associated with our commodity, interest rate and weather derivative instruments were recorded in our condensed consolidated statements of operations as follows (in thousands): Three months ended March 31, Statement of Operations Classification Realized Unrealized 2018 Gains (losses) on commodity derivatives, net $ 119 $ (59 ) Interest expense 1,350 5,171 Direct operating expenses (278 ) — Total $ 1,191 $ 5,112 2017 Gains (losses) on commodity derivatives, net $ 420 $ (55 ) Interest expense (65 ) (317 ) Direct operating expenses (257 ) — Total $ 98 $ (372 )

Property, Plant and Equipment

Property, Plant and Equipment	3 Months Ended
	Mar. 31, 2018
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	(8) Property, Plant and Equipment Property, plant and equipment, net, consists of the following (in thousands): Useful Life (in years) March 31, December 31, Land Infinite $ 16,366 $ 18,145 Construction in progress N/A 83,013 55,622 Buildings and improvements 4 to 40 15,476 16,235 Transportation equipment 5 to 15 22,597 22,697 Processing and treating plants 8 to 40 123,580 123,138 Pipelines, compressors and right-of-way 3 to 40 975,213 974,301 Storage 3 to 40 124,037 146,105 Equipment 3 to 31 61,935 80,220 Total property, plant and equipment 1,422,217 1,436,463 Accumulated depreciation (341,320 ) (340,878 ) Property, plant and equipment, net $ 1,080,897 $ 1,095,585 At March 31, 2018 and December 31, 2017 , gross property, plant and equipment included $369.5 million and $367.6 million , respectively, related to our FERC regulated interstate and intrastate assets. Depreciation and amortization expense totaled $18.6 million and $18.5 million for the three months ended March 31, 2018 and 2017 , respectively. Capitalized interest was $0.6 million and $1.0 million the three months ended March 31, 2018 and 2017 , respectively.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	(9) Goodwill and Intangible Assets Goodwill consists of the following (in thousands): March 31, 2018 December 31, 2017 Liquid Pipelines and Services $ 35,710 $ 35,708 Terminalling Services 27,303 88,466 Offshore Pipeline and Services 4,972 4,692 Total $ 67,985 $ 128,866 The change in goodwill in our Terminalling Services segment relates to goodwill on our Refined Products Business that was classified as held for sale at March 31, 2018, see Note 4 - Acquisitions and Dispositions. Intangible assets, net, consists of customer relationships, dedicated acreage agreements, collaborative arrangements, noncompete agreements and trade names. These intangible assets have definite lives and are subject to amortization on a straight-line basis over their economic lives, currently ranging from approximately 5 years to 30 years . Intangible assets, net, consist of the following (in thousands): March 31, 2018 Gross carrying amount Accumulated amortization Net carrying amount Customer relationships $ 64,744 $ (14,806 ) $ 49,938 Customer contracts 94,692 (49,420 ) 45,272 Dedicated acreage 42,547 (6,560 ) 35,987 Collaborative arrangements 11,884 (1,627 ) 10,257 Noncompete agreements 1,064 (1,064 ) — Other 198 (25 ) 173 Total $ 215,129 $ (73,502 ) $ 141,627 December 31, 2017 Gross carrying amount Accumulated amortization Net carrying amount Customer relationships $ 110,483 $ (29,965 ) $ 80,518 Customer contracts 94,692 (48,173 ) 46,519 Dedicated acreage 42,547 (6,216 ) 36,331 Collaborative arrangements 11,884 (1,415 ) 10,469 Noncompete agreements 1,064 (1,064 ) — Other 198 (25 ) 173 Total $ 260,868 $ (86,858 ) $ 174,010 Amortization expense related to our intangible assets totaled $2.7 million and $6.6 million for the three months ended March 31, 2018 and 2017 , respectively. The estimated aggregate annual amortization expected to be recognized for the remainder of 2018 and each of the four succeeding fiscal years is $7.6 million , $10.2 million , $10.2 million , $10.2 million and $9.3 million , respectively.

Investment in Unconsolidated Af

Investment in Unconsolidated Affiliates	3 Months Ended
	Mar. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Investment in Unconsolidated Affiliates	(10) Investments in unconsolidated affiliates The following table presents the activity in our equity method investments in unconsolidated affiliates (in thousands): Delta House (1) Emerald Transactions FPS (3) OGL (3) Destin (3) Tri-States (2) Okeanos (3) Wilprise (2) Cayenne JV (2) Total Ownership % - 12/31/2017 35.7 % 35.7 % 66.7 % 16.7 % 66.7 % 25.3% 50.0 % Ownership % - 3/31/2018 35.7 % 35.7 % 66.7 % 16.7 % 66.7 % 25.3% 50.0 % Balances at December 31, 2017 $ 90,412 $ 46,932 $ 124,245 $ 53,057 $ 22,445 $ 4,689 $ 6,654 $ 348,434 Earnings in unconsolidated affiliates 3,227 2,715 2,377 854 2,132 258 1,110 12,673 Contributions — — — — — — 2,018 2,018 Distributions (2,247 ) (4,278 ) (10,734 ) (2,034 ) (4,378 ) (183 ) — (23,854 ) Balances at March 31, 2018 $ 91,392 $ 45,369 $ 115,888 $ 51,877 $ 20,199 $ 4,764 $ 9,782 $ 339,271 ___________________________________________________ (1) Represents direct and indirect ownership interests in Class A units and common units. FPS denotes Floating Production System LLC whereas OGL denotes Oil & Gas Lateral LLC. (2) Included in our Liquid Pipelines and Services segment. (3) Included in our Offshore Pipelines and Services segment. The following tables present the summarized combined financial information for our equity investments (amounts represent 100% of investee financial information) (in thousands): Balance Sheets: March 31, 2018 December 31, 2017 Current assets $ 64,381 $ 80,405 Non-current assets 1,279,417 1,288,862 Current liabilities 114,724 130,904 Non-current liabilities $ 438,496 $ 436,584 Three months ended March 31, Statements of Operations: 2018 2017 Revenue $ 56,898 $ 93,870 Operating expenses 6,292 8,436 Net income $ 32,845 $ 69,285

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	3 Months Ended
	Mar. 31, 2018
Other Liabilities Disclosure [Abstract]
Accrued Expenses and Other Current Liabilities	(11) Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consists of the following (in thousands): March 31, 2018 December 31, 2017 Capital expenditures $ 20,880 $ 10,721 Accrued interest 15,590 3,190 Convertible preferred unit distributions 8,354 — Employee compensation 149 90 Current portion of asset retirement obligation 6,416 6,416 Additional Blackwater acquisition consideration 5,000 5,000 Transaction costs 3,732 3,408 Customer deposits 1,136 1,109 Taxes payable 4,018 5,263 Due to related parties 3,212 6,609 Deferred financing costs — 266 Contingent liabilities associated with VKGS and Panther 2,098 2,099 Royalties, gas imbalance and leases payables 7,119 7,905 Professional fees 2,024 1,848 Accrued corporate expenses 1,697 2,487 Accrued operating expenses 4,881 6,609 Other 1,817 5,834 Total accrued expenses and other current liabilities $ 88,123 $ 68,854

Asset Retirement Obligations

Asset Retirement Obligations	3 Months Ended
	Mar. 31, 2018
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement Obligations	(12) Asset Retirement Obligations We record a liability for the fair value of asset retirement obligations and conditional asset retirement obligations (collectively referred to as “AROs”) that we can reasonably estimate, on a discounted basis, in the period in which the liability is incurred. Generally, the fair value of the liability is calculated using discounted cash flow techniques and based on internal estimates and assumptions related to (i) future retirement costs, (ii) future inflation rates, and (iii) credit-adjusted risk-free interest rates. Significant increases or decreases in the assumptions would result in a significant change to the fair value measurement. Certain assets related to our Offshore Pipelines and Services segment have regulatory obligations to perform remediation, and in some instances dismantlement and removal activities when the assets are abandoned. These AROs include varying levels of activity including disconnecting inactive assets from active assets, cleaning and purging assets, and in some cases, completely removing the assets and returning the land to its original state. These assets have been in existence for many years and with regular maintenance will continue to be in service for many years to come. It is not possible to predict when demand for these transmission services will cease, however, we do not believe that such demand will cease for the foreseeable future. The majority of the current portion of our AROs, which is included in Accrued Expenses and Other Current Liabilities in our condensed consolidated balance sheet, is related to the retirement of the Midla pipeline discussed in Note 13 - Debt Obligations. The following table presents activity in our asset retirement obligations for the three months ended March 31, 2018 (in thousands): Non-current balance $ 66,194 Current balance 6,416 Balances at December 31, 2017 $ 72,610 Additions 260 Expenditures — Accretion expense 440 Balances at March 31, 2018 $ 73,310 Less: current portion 6,416 Noncurrent asset retirement obligation $ 66,894 ___________________________________________________ We are required to establish security against potential obligations relating to the abandonment of certain transmission assets that may be imposed on the previous owner by applicable regulatory authorities. We have deposited $5.0 million with a third party to secure our performance on these potential obligations. These deposits are included in Restricted cash-long term in our condensed consolidated balance sheets as of March 31, 2018 and December 31, 2017.

Debt Obligations

Debt Obligations	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Debt Obligations	(13) Debt Obligations Our outstanding debt consists of the following (in thousands): March 31, 2018 December 31, 2017 Revolving credit facility $ 712,600 $ 697,900 8.50% Senior unsecured notes, due 2021 425,000 425,000 3.77% Senior secured notes, due 2031 (non-recourse) 57,817 58,324 3.97% Senior secured notes, due 2032 (non-recourse) 31,586 32,025 Other debt (1) 2,431 4,989 Total debt obligations 1,229,434 1,218,238 Unamortized debt issuance costs (2) (9,530 ) (9,231 ) Total debt 1,219,904 1,209,007 Less: Current portion, including unamortized debt issuance costs (5,058 ) (7,551 ) Long term debt $ 1,214,846 $ 1,201,456 ___________________________ (1) Other debt includes miscellaneous long-term obligations, which are reported in Other liabilities line items on our condensed consolidated balance sheets. (2) Unamortized debt issuance costs related to the revolving credit facility are included in our condensed consolidated balance sheets in Other assets, net. AMID Revolving Credit Agreement On March 8, 2017, the Partnership, along with other subsidiaries of the Partnership (collectively, the “Borrowers”) entered into the Second Amended and Restated Credit Agreement, with Bank of America N.A., as Administrative Agent, Collateral Agent and L/C Issuer, Wells Fargo Bank, National Association, as Syndication Agent, and other lenders (the “Credit Agreement” or “revolving credit facility”), which increased the Borrowers’ borrowing capacity thereunder from $750.0 million to $900.0 million and provided for an accordion feature that will permit, subject to customary conditions, the borrowing capacity under the facility to be increased to a maximum of $1.1 billion . The $900 million in lending commitments under the Credit Agreement includes a $30 million sublimit for borrowings by Blackwater Investments, Inc. and a $100 million sublimit for letters of credit. The Credit Agreement matures on September 5, 2019. All obligations under the Credit Agreement and the guarantees of those obligations are secured, subject to certain exceptions, by a first-priority lien on and security interest in (i) substantially all of the Borrowers’ assets and the assets of certain of the subsidiaries of the Partnership and (ii) the capital stock of certain of the Partnership’s subsidiaries. We can elect to have loans under our Credit Agreement bear interest either at (a) a Eurodollar-based rate, plus a margin ranging from 2.00% to 3.25% depending on our total leverage ratio then in effect, or (b) a base rate which is a fluctuating rate per annum equal to the highest of (i) the Federal Funds Rate plus 0.50% , (ii) the rate of interest in effect for such day as publicly announced from time to time by Bank of America as its "prime rate," and (iii) a Eurodollar-based rate plus 1.00% , in each case of clause (i)-(iii), 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 ranging from 0.375% to 0.50% per annum, depending on our total leverage ratio then in effect, on the undrawn portion of the revolving loan under the Credit Agreement. Borrowings under the Second Amended and Restated Credit Agreement are guaranteed on a senior unsecured basis by certain of our subsidiaries (the “Guarantors”). The guarantees by the Guarantors 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 and any accrued and unpaid interest will be due and payable in full at maturity, on September 5, 2019. The Credit Agreement contains certain financial covenants that are applicable as of the end of any fiscal quarter, including a consolidated total leverage ratio which requires our indebtedness not to exceed 5.00 times adjusted consolidated EBITDA (provided that the minimum consolidated total leverage may be increased to 5.50 times adjusted consolidated EBITDA in connection with the closing of certain material acquisitions as of the end of the quarter during which such acquisition closes, and as of the end of the subsequent two quarters), a consolidated secured leverage ratio which requires our secured indebtedness not to exceed 3.50 times adjusted consolidated EBITDA, and a minimum interest coverage ratio that requires our adjusted consolidated EBITDA to exceed consolidated interest charges by not less than 2.50 times. In the first three quarters of 2017, we were in compliance with the total leverage ratio covenant of 5.50 times, 5.50 times and 5.00 times, for quarter periods ended March 31, 2017, June 30, 2017 and September 30, 2017, respectively, as described above. During the fourth quarter of 2017, we elected to be in a Specified Acquisition Period, as defined in Section 7.19 Financial Covenants of the Credit Agreement, which enables us to use a ratio of 5.50 times for the fourth quarter of 2017 as well as the first and second quarters of 2018. As of March 31, 2018, our consolidated total leverage ratio was 5.19 , our consolidated secured leverage ratio was 3.30 , and our interest coverage ratio was 3.43 , all of which were in compliance with the related covenants of our Credit Agreement. At March 31, 2018, letters of credit outstanding under the Credit Agreement were $31.0 million . As of March 31, 2018, we had approximately $712.6 million of borrowings outstanding. The carrying value of amounts outstanding under the Credit Agreement approximates the related fair value, as interest charges vary with market rates conditions. Our ability to maintain compliance with the leverage and interest coverage ratios included in the Credit Agreement may be subject to, among other things, the timing and success of initiatives we are pursuing, which may include expansion capital projects, acquisitions or drop down transactions, as well as the associated financing for such initiatives. The terms of the Credit Agreement also include covenants that restrict our ability to make cash distributions and acquisitions in some circumstances. If required, ArcLight , which controls the General Partner of the Partnership, has confirmed its intent to provide financial support for the Partnership to maintain compliance with the covenants contained in the Credit Agreement through April 10, 2019. 8.50% Senior Unsecured Notes On December 28, 2016, the Partnership and American Midstream Finance Corporation, our wholly-owned subsidiary (the “Co-Issuer” and together with the Partnership, the “Issuers”), completed the issuance and sale of $300 million aggregate principal amount of their 8.50% Senior Notes due 2021 (the "8.50% Senior Notes"). The 8.50% Senior Notes are jointly and severally guaranteed by the Guarantors. The 8.50% Senior Notes rank equal in right of payment with all existing and future senior indebtedness of the Issuers, and senior in right of payment to any future subordinated indebtedness of the Issuers. The 8.50% Senior Notes were issued at par and provided approximately $294.0 million in proceeds, after deducting the initial purchasers' discount of $6.0 million . The Partnership also incurred $2.7 million of direct issuance costs resulting in net proceeds related to the 8.50% Senior Notes of $291.3 million . The 8.50% Senior Notes were offered and sold to qualified institutional buyers in the United States pursuant to Rule 144A under the Securities Act, and to persons, other than U.S. persons, outside the United States pursuant to Regulation S under the Securities Act. Upon the closing of the JPE Merger and the satisfaction of other conditions related thereto, the restricted cash was released from escrow and was used to repay the JPE’s revolving credit facility and to reduce borrowings under the Partnership’s Credit Agreement. On December 19, 2017, the Issuers completed the issuance and sale of an additional $125 million in aggregate principal amount of 8.50% Senior Notes (the “Additional Issuance”), net of issuance cost of approximately $3.0 million . The Additional Issuance was offered and sold to qualified institutional buyers in the United States pursuant to Rule 144A under the Securities Act, and to persons, other than U.S. persons, outside the United States pursuant to Regulation S under the Securities Act. None of the 8.50% Senior Notes, including the Additional Issuance, have been registered under the Securities Act. The 8.50% Senior Notes will mature on December 15, 2021 and interest on the Additional Issuance will accrue from December 15, 2017. Interest on the 8.50% Senior Notes is payable in cash semiannually in arrears on each June 15 and December 15, with interest payable on the Additional Issuance commencing June 15, 2018. Interest will be payable to holders of record on the June 1 and December 1 immediately preceding the related interest payment date and will be computed on the basis of a 360-day year consisting of twelve 30-day months. Pursuant to the registration rights agreements entered into in connection with the issuances of the 8.50% Senior Notes, additional interest on the 8.50% Senior Notes accrues at 0.25% per annum for the first 90-day period following December 23, 2017 and by an additional 0.25% per annum with respect to each subsequent 90-day period, up to a maximum additional rate of 1.00% per annum over 8.50%, until we complete an exchange offer for the 8.50% Senior Notes. At any time prior to December 15, 2018, the Issuers may redeem up to 35% of the aggregate principal amount of 8.50% Senior Notes, at a redemption price of 108.50% of the principal amount, plus accrued and unpaid interest to the redemption date, in an amount not greater than the net cash proceeds of one or more equity offerings by the Partnership, provided that: • at least 65% of the aggregate principal amount of the 8.50% Senior Notes remains outstanding immediately after such redemption (excluding 8.50% Senior Notes held by the Partnership and its subsidiaries); and • the redemption occurs within 180 days of the closing of each such equity offering. On and after December 15, 2018, the Issuers may redeem all or a part of the 8.50% Senior Notes, at the redemption prices (expressed as percentages of principal amount) set forth below, plus accrued and unpaid interest, if redeemed during the twelve-month period beginning on December 15 of the years indicated below: Year Percentage 2018 104.250% 2019 102.125% 2020 and thereafter 100.000% The Indenture restricts the Partnership’s ability and the ability of certain of its subsidiaries to, among other things: (i) incur, assume or guarantee additional indebtedness, issue any disqualified stock or issue preferred units, (ii) create liens to secure indebtedness, (iii) pay distributions on equity securities, redeem or repurchase equity securities or redeem or repurchase subordinated securities, (iv) make investments, (v) restrict distributions, loans or other asset transfers from restricted subsidiaries, (vi) consolidate with or merge with or into, or sell substantially all of its properties to, another person, (vii) sell or otherwise dispose of assets, including equity interests in subsidiaries, (viii) enter into transactions with affiliates, (ix) engage in certain business activities and (x) enter into sale and leaseback transactions. These covenants are subject to a number of important exceptions and qualifications. If at any time the 8.50% Senior Notes are rated investment grade by either Moody’s Investors Service, Inc. or Standard & Poor’s Ratings Services and no Default or Event of Default (as each are defined in the Indenture) has occurred and is continuing, many of such covenants will terminate and the Partnership and its subsidiaries will cease to be subject to such covenants. The carrying value of the 8.50% Senior Notes as of March 31, 2018 is $ 418.1 million , which approximates the fair value as of that date of $430.4 million . This estimate was based on similar private placement transactions along with changes in market interest rates which represent a Level 2 measurement. 3.77% Senior Secured Notes On September 30, 2016, Midla Financing, LLC ("Midla Financing"), American Midstream (Midla), LLC (“Midla”), and MLGT and together with Midla, (the "Note Guarantors"), entered into the 3.77% Senior Note Purchase and Guaranty Agreement (the “Note Purchase Agreement”) with certain institutional investors (the “Purchasers”) whereby Midla Financing issued $60.0 million in an aggregate principal amount of 3.77% Senior Notes (non-recourse) due June 30, 2031. Principal and interest on the 3.77% Senior Notes is payable in installments on the last business day of each quarter beginning June 30, 2017 with the remaining balance payable in full on June 30, 2031. The average quarterly principal payment is approximately $1.1 million . The 3.77% Senior Notes were issued at par and provided net proceeds of approximately $57.7 million , net of debt issuance costs of $2.3 million . Net proceeds from the 3.77% Senior Notes are restricted and will be used to fund project costs incurred in connection with the construction of the Midla-Natchez Line, the retirement of Midla’s existing 1920’s pipeline, the move of our Baton Rouge operations to the MLGT system, and the reconfiguration of the DeSiard compression system and all related ancillary facilities. These proceeds can also be used to pay costs incurred in connection with the issuance of the 3.77% Senior Notes, and for the general corporate purposes of Midla Financing. As of March 31, 2018 , Restricted cash includes $15.2 million from the issuance of the 3.77% Senior Notes. The Note Purchase Agreement includes representations and warranties, affirmative and negative covenants (including financial covenants), and events of default that are customary for a transaction of this type. Midla Financing must maintain a debt service reserve account containing six months of principal and interest payments. In connection with the Note Purchase Agreement, the Note Guarantors guaranteed the payment in full of all Midla Financing’s obligations under the Note Purchase Agreement. Also, Midla Financing and the Note Guarantors granted a security interest in substantially all of their tangible and intangible personal property, including the membership interests in each Note Guarantor held by Midla Financing, and Midla Holdings pledged the membership interests in Midla Financing to the Collateral Agent. The 3.77% Senior Notes are non-recourse to the Partnership. As of March 31, 2018, the fair value of the 3.77% Senior Notes was $51.8 million . This estimate was based on similar private placement transactions along with changes in market interest rates which represent a Level 2 measurement. 3.97% Trans-Union Secured Senior Notes On May 10, 2016, Trans-Union Interstate Pipeline, LP ("Trans-Union") entered into an agreement with certain institutional investors in the insurance business represented by Babson Capital Management LLC whereby Trans-Union issued $35.0 million in an aggregate principal amount of 3.97% Senior Secured Notes ("Trans-Union Senior Notes") due December 31, 2032. Principal and interest on the Trans-Union Senior Notes is payable in installments on the last business day of each quarter beginning June 30, 2016 with the remaining balance payable in full on December 31, 2032. The average quarterly principal payment is approximately $0.5 million . The Trans-Union Senior Notes were originally issued at par and provided net proceeds of approximately $34.6 million after deducting related issuance cost of approximately $0.4 million . The Partnership assumed the Trans-Union Senior Notes following the Trans-Union acquisition on November 3, 2017. As of March 31, 2018, the fair value of the 3.97% Senior Notes was approximately $28.7 million . This estimate was based on similar private placement transactions along with changes in market interest rates which represent a Level 2 measurement.

Convertible Preferred Units (No

Convertible Preferred Units (Notes)	3 Months Ended
	Mar. 31, 2018
Partners' Capital [Abstract]
Convertible Preferred Units	(14) Convertible Preferred Units Our convertible preferred units consist of the following (in thousands): Series A Series C Total Units $ Units $ $ December 31, 2017 10,719 $ 191,798 8,965 $ 125,382 $ 317,180 Paid in kind unit distributions 291 — 277 — — March 31, 2018 11,010 $ 191,798 9,242 $ 125,382 $ 317,180 Affiliates of our General Partner hold and participate in quarterly distributions on our convertible preferred units, with such distributions being made in cash, paid-in-kind units or a combination thereof, at the election of the Board of Directors of our General Partner. The convertible preferred unitholders have the right to receive cumulative distributions in the same priority and prior to any other distributions made in respect of any other partnership interests. To the extent that any portion of a quarterly distribution on our convertible preferred units to be paid in cash exceeds the amount of cash available for such distribution, the amount of cash available will be paid to our convertible preferred unitholders on a pro rata basis while the difference between the distribution and the available cash will become arrearages and accrue interest until paid. Series A-1 Convertible Preferred Units On April 15, 2013, the Partnership, our General Partner and AIM Midstream Holdings LLC entered into agreements with HPIP, pursuant to which HPIP acquired 90% of our General Partner and all of our subordinated units from AIM Midstream Holdings and contributed the High Point System, our 574 mile transmission system located in southeast Louisiana and the Gulf of Mexico, and $15.0 million in cash to us in exchange for 5,142,857 of our Series A-1 Units. The holders of Series A-1 Units receive distributions prior to any distributions to our common unitholders. The distributions on the Series A-1 Units are equal to the greater of $0.4125 per unit or the declared distribution to common unitholders. The Series A-1 Units may be converted into common units, subject to customary anti-dilutive adjustments, at the option of the unitholders at any time. As of March 31, 2018 , the conversion price was $15.16 and the conversion ratio is 1 to 1.1483 . Series A-2 Convertible Preferred Units On March 30, 2015 and June 30, 2015, we entered into two Series A-2 Convertible Preferred Unit Purchase Agreements with Magnolia Infrastructure Partners, an affiliate of HPIP pursuant to which we issued, in separate private placements, newly-designated Series A-2 Units (the “Series A-2 Units”) representing limited partnership interests in the Partnership. As a result, the Partnership issued a total of 2,571,430 Series A-2 Units for approximately $45.0 million in aggregate proceeds during the year ended December 31, 2015. The Series A-2 Units will participate in distributions of the Partnership along with common units in a manner identical to the existing Series A-1 Units (together with the Series A-2 Units, the "Series A Units"), with such distributions being made in cash or with paid-in-kind Series A Units at the election of the Board of Directors of our General Partner. On July 27, 2015, we amended our Partnership Agreement to grant us the right (the “Call Right”) to require the holders of the Series A-2 Units to sell, assign and transfer all or a portion of the then-outstanding Series A-2 Units to us for a purchase price of $17.50 per Series A-2 Unit (subject to appropriate adjustment for any equity distribution, subdivision or combination of equity interests in the Partnership). We may exercise the Call Right at any time, in connection with our or our affiliates’ acquisition of assets or equity from ArcLight Energy 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 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 we may also not exercise the Call Right if doing so would result in a default under any of our or our affiliates’ financing agreements or obligations. As of March 31, 2018 , the conversion price was $15.16 and the conversion ratio is 1 to 1.1483 . Series C Convertible Preferred Units On April 25, 2016, we issued 8,571,429 Series C Units to an ArcLight affiliate in connection with the purchase of membership interests in certain midstream entities. The Series C Units have voting rights that are identical to the voting rights of the common units and will vote with the common units as a single class on an as converted basis, with each Series C Unit initially entitled to one vote for each common unit into which such Series C Unit is convertible. The Series C Units also have separate class voting rights on any matter, including a merger, consolidation or business combination, that adversely affects, amends or modifies any of the rights, preferences, privileges or terms of the Series C Units. The Series C Units are convertible in whole or in part into common units at any time. The number of common units into which a Series C Unit is convertible will be an amount equal to the sum of $14.00 plus all accrued and accumulated but unpaid distributions, divided by the conversion price. The sale of the Series C Units was exempt from registration under the Securities Act of 1933, as amended (the “Securities Act”) pursuant to Rule 4(a)(2) under the Securities Act. In the event that we issue, sell or grant any common units or convertible securities at an indicative per common unit price that is less than $14.00 per common unit (subject to customary anti-dilution adjustments), then the conversion price will be adjusted according to a formula to provide for an increase in the number of common units into which Series C Units are convertible. As of March 31, 2018 , the conversion price was $13.33 and the conversion ratio is 1 to 1.0448 . In connection with the issuance of the Series C Units, we issued the holders a warrant to purchase up to 800,000 common units at an exercise price of $7.25 per common unit (the "Series C Warrant"). The Series C Warrant is subject to standard anti-dilution adjustments and is exercisable for a period of seven years. The fair value of the Series C Warrant was determined using a market approach that utilized significant inputs which are not observable in the market and thus represent a Level 3 measurement as defined by ASC 820. The estimated fair value of $4.41 per warrant unit was determined using a Black-Scholes model and the following significant assumptions: (i) a dividend yield of 18% , (ii) common unit volatility of 42% and (iii) the seven -year term of the warrant to arrive at an aggregate fair value of $4.5 million . As conversion is at the option of the holder and redemption is contingent upon a future event which is outside the control of the Partnership, the Series A-1, A-2 and C Units have been classified as mezzanine equity in the condensed consolidated balance sheets.

Partners Capital

Partners Capital	3 Months Ended
	Mar. 31, 2018
Equity [Abstract]
Partners’ Capital	(15) Partners’ Capital Our capital accounts are comprised of approximately 1.3% notional General Partner interests and 98.7% limited partner interests as of March 31, 2018 . Our limited partners have limited rights of ownership as provided for under our Partnership Agreement and the right to participate in our distributions. Our General Partner manages our operations and participates in our distributions, including certain incentive distributions pursuant to the incentive distribution rights that are non-voting limited partner interests held by our General Partner. Pursuant to our Partnership Agreement, our General Partner participates in losses and distributions based on its interest. The General Partner’s participation in the allocation of losses and distributions is not limited and therefore, such participation can result in a deficit to its capital account. As such, allocation of losses and distributions, including distributions for previous transactions between entities under common control, has resulted in a deficit to the General Partner’s capital account included in our condensed consolidated balance sheets. Outstanding Units The following table presents unit activity (in thousands): General Limited Partner Interest Balances at December 31, 2017 965 52,711 LTIP vesting — 142 Balances at March 31, 2018 965 52,853 General Partner Units In order for our General Partner to maintain its ownership percentage in us, our general partner paid $0.1 million for the issuance of 8,665 additional notional General Partner units for the three months ended March 31, 2017. We received no such proceeds from our General Partner and issued no additional General Partner units for the three months ended March 31, 2018. Distributions Preferred Units Distributions are accrued in the current quarter under the terms of the Partnership’s Fifth Amended and Restated Agreement of Limited Partnership, as amended. Such distributions are generally declared and paid in the following quarter in the form of cash or paid-in-kind (“PIK”) units, or any combination thereof. Distributions for the first quarter 2018 were accrued and were paid fully in cash in the second quarter 2018. Distributions in the first quarter 2017 reflect both cash and PIK payments made for distributions that were accrued in the fourth quarter 2016, and the accrual of cash and PIK units that were paid in the second quarter 2017. Limited Partner Units (Common Units) The distribution related to the Limited Partner units, which was declared and paid in the first quarter 2018, was 100% cash. We made the following distributions (in thousands): Three months ended March 31, 2018 2017 Series A Units Cash Paid $ — $ 2,527 Accrued (1) 4,542 4,296 Paid-in-kind units — 2,733 Series C Units Cash Paid — 3,627 Accrued (1) 3,812 3,627 Paid-in-kind units — — Series D Units Cash Paid — 962 Accrued — 962 Limited Partner Units Cash Paid 21,745 24,915 General Partner Units Cash Paid 290 167 Summary Cash Paid 22,035 32,198 Accrued (1) 8,354 8,885 Paid-in-kind units — 2,733 (1) Can include either Cash, PIK or a combination of both. Fair value determination of PIK of Preferred Units The fair value of the PIK distributions was determined using the market and income approaches, requiring significant inputs which are not observable in the market and thus represent a Level 3 measurement as defined by ASC 820. Under the income approach, the fair value estimates for all periods presented were based on (i) present value of estimated future contracted distributions, (ii) option values ranging from $0.31 per unit to $2.83 per unit using a Black-Scholes model, (iii) assumed discount rates ranging from 5.57% to 6.23% and (iv) assumed growth rates of 1.0% .

Net Loss per Limited Partner Un

Net Loss per Limited Partner Unit	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Net Loss per Limited Partner Unit	(16) Net loss per Limited Partner Unit As discussed in Note 4 - Acquisitions and Dispositions , the JPE Merger on March 8, 2017 was a combination between entities under common control. As a result, prior periods were retrospectively adjusted to furnish comparative information. Accordingly, the prior period earnings combining both entities were allocated among our General Partners and common unitholders assuming JPE units were converted into our common units in the comparative historical periods. The calculation of basic and diluted limited partners' net loss per common unit is summarized below (in thousands, except per unit amounts): Three months ended March 31, 2018 2017 Loss from continuing operations $ (13,838 ) $ (28,171 ) Less: Net income attributable to noncontrolling interests 45 1,303 Loss attributable to the Partnership (13,883 ) (29,474 ) Less: Distributions on Series A Units 4,542 4,296 Distributions on Series C Units 3,812 3,627 Distributions on Series D Units — 962 General Partner's distribution 290 200 General Partner's share in undistributed loss (583 ) (560 ) Loss attributable to Limited Partners (21,944 ) (37,999 ) Loss from discontinued operations, net of tax — (710 ) Net loss attributable to Limited Partners $ (21,944 ) $ (38,709 ) Weighted average number of common units outstanding - Basic and Diluted 52,769 51,451 Limited Partners' net loss per common unit - Basic and Diluted Loss from continuing operations $ (0.42 ) $ (0.74 ) Loss from discontinued operations — (0.01 ) Net loss (1) $ (0.42 ) $ (0.75 ) _____________________________________ (1) Potential common unit equivalents are antidilutive for all periods presented and, as a result, have been excluded from the determination of diluted limited partners' net loss per common unit.

Incentive Compensation

Incentive Compensation	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Incentive Compensation	(17) Incentive Compensation Unit-based Compensation All equity-based awards issued under the long-term incentive plan (“LTIP”) consist of phantom units, distribution equivalent rights (“DERs”) or option grants. DERs and options have been granted on a limited basis to executives. Future awards may be granted at the discretion of the Compensation Committee of our General Partner’s Board of Directors (the “Board”) and subject to approval by the Board. At March 31, 2018 , there were 4,308,985 common units available for future grants under the LTIP. Phantom Unit Awards . Under the LTIP, phantom units typically vest in increments of 25% on each grant anniversary date and do not contain any vesting requirements other than continued employment. During the three months ended March 31, 2018 there were 38,000 , 154,693 and 193,698 of phantom units granted, forfeited and vested, respectively, which weighted-average grant date fair value per unit was $11.88 , $7.12 and $4.49 , respectively. The fair value of our phantom units (“RSUs”) is based on the fair value of our common units at the grant date, discounted to reflect the fact that the RSUs are not eligible for the quarterly distribution prior to complete vesting (usually 25% per year over 4 years ). Compensation expenses related to RSUs were $ 0.7 million and $4.0 million for the three months ended March 31, 2018 and 2017, respectively, and are included in Corporate expenses and Direct operating expenses in our condensed consolidated statements of operations and Equity compensation expense in our condensed consolidated statements of changes in partners’ capital and noncontrolling interests. Option to Purchase Common Units There were no grants of options in the quarter ended March 31, 2018. The compensation expense related to option awards for each of the three months ended March 31, 2018 and 2017 was immaterial. As of March 31, 2018, there were 245,000 unvested options the unrecognized compensation expense of which was $0.1 million . Performance Based Awards (PSUs) There were no new grants of PSUs during the first quarter of 2018. The compensation expense related to PSU awards for the three months ended March 31, 2018 and 2017 was $0.3 million and zero , respectively. As of March 31, 2018, there were 524,000 unvested PSUs the unrecognized compensation expense of which was $5.9 million . Defined Contribution Plan For the three months ended March 31, 2018 and 2017, the compensation expense associated with our defined contribution plan 401(k)’s employer matching was $0.8 million and $0.5 million , respectively. There was no change to the defined contribution plan.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	(18) 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 in our 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. Other Commitments The expenses associated with our operating leases and service contracts for the three months ended March 31, 2018 and 2017 was $2.6 million and $1.9 million , respectively.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	(19) Related Party Transactions To the extent applicable, our discussion below includes the nature of our relationship and activities that we had with our Related Parties, as defined and required by ASC 850 - Related Party Disclosures, as of and for the three months ended March 31, 2018 and 2017 and the outstanding balances as of March 31, 2018 and December 31, 2017. Balances associated with our investments in unconsolidated affiliates are disclosed in Note 10 - Investments in unconsolidated affiliates. Blackwater Midstream Holdings, LLC In December 2013, we acquired Blackwater Midstream Holdings, LLC (“Blackwater”) from an affiliate of ArcLight. The acquisition agreement included a provision whereby an ArcLight affiliate would be entitled to an additional $5.0 million of merger consideration based on Blackwater meeting certain operating targets. We determined that it was probable the operating targets would be met in 2018 and have kept a $5.0 million accrued distribution to the ArcLight affiliate which is included in Accrued expense and other current liabilities in the accompanying consolidated balance sheets. Republic Midstream, LLC Republic Midstream, LLC (“Republic”), is an entity owned by ArcLight to which we historically charged a monthly fee of approximately $0.1 million . The services agreement with Republic terminated according to its terms in September 2017 and services are no longer provided to Republic. As of March 31, 2018 and December 31, 2017, we had an accounts receivable balance due from Republic of $0.1 million and $0.8 million , respectively, which is included in Other current assets in the accompanying balance sheets. General Partner Our General Partner paid $9.9 million related to corporate overhead support which was presented as part of the contribution line item in Cash flows from financing activities in our consolidated statements of cash flows. As of March 31, 2018 and December 31, 2017, we had $3.7 million and $6.5 million , respectively, of accounts payable due to our General Partner, which has been recorded in Accrued expenses and other current liabilities and relates primarily to compensation. This payable/receivable is generally settled on a quarterly basis related to the foregoing transactions. On March 11, 2018, the Partnership and Magnolia, an affiliate of ArcLight, entered into a Capital Contribution Agreement (the “Capital Contribution Agreement”) to provide additional capital and overhead support to us during the first three quarters of 2018 in connection with temporary curtailment of production flows at the Delta House platform (“Delta House”). Pursuant to the Capital Contribution Agreement, Magnolia has agreed to provide quarterly capital contributions, in an amount to be agreed, up to the difference between the actual cash distribution received by us on account of our interest in Delta House and the quarterly cash distribution expected to be received had the production flows to Delta House not been curtailed. Subsequent to March 31, 2018, in accordance with this agreement Magnolia agreed to an additional capital contribution of $9.4 million , which was paid in the second quarter of 2018. Destin and Okeanos On November 1, 2016, we became operator of the Destin and Okeanos pipelines and entered into operating and administrative management agreements under which our affiliates pay a monthly fee for general and administrative services provided by us. In addition, the affiliates reimburse us for certain transition related expenses. For the three months ended March 31, 2018 and 2017, we recognized $0.6 million of management fee income for each respective period. As of March 31, 2018 and December 31, 2017, we had an outstanding accounts receivable balance of $2.5 million and $0.9 million , respectively, which is included in Other current assets in the accompanying balance sheets. Consolidated Asset Management Services, LLC ("CAMS") Dan Revers, a director of our General Partner, indirectly owns in excess of 22% of CAMS, which, through various subsidiaries or affiliates, provides pipeline integrity services to the Partnership and subleases an office space from the Partnership. During the three months ended March 31, 2018 and 2017, the Partnership was invoiced by CAMS $0.1 million for each respective period, and had no outstanding accounts receivable balance as of March 31, 2018 or December 31, 2017. Other Related Party Transactions Michael D. Rupe, the brother of Ryan Rupe (the Partnership’s Vice President - Natural Gas Services and Offshore Pipelines), is the Chief Financial Officer of CIMA Energy Ltd., a crude oil and natural gas marketing company (“CIMA”). The Partnership regularly engages in purchases and sales of crude oil and natural gas with CIMA. During the three months ended March 31, 2018 , the Partnership invoiced CIMA $2.1 million and received invoicing from CIMA of $0.7 million in connection with such transactions. For the three months ended March 31, 2017, the Partnership invoiced CIMA $1.4 million and received invoices from CIMA of $0.7 million for services. As of March 31, 2018 and December 31, 2017, the Partnership had no outstanding amounts due from or to CIMA. During September and October 2017, under a transition services agreement, the Partnership made payments on behalf of AMID Merger GP II, LLC related to the Propane Business sale. As of March 31, 2018 and December 31, 2017, we had an outstanding accounts receivable balance related to these payments of $2.5 million , respectively, which is included in Other current assets in the accompanying balance sheets.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information (Notes)	3 Months Ended
	Mar. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	(20) Supplemental Cash Flow Information Supplemental cash flows and non-cash transactions consist of the following (in thousands): Three months ended March 31, 2018 2017 Supplemental cash flow information Interest payments, net of capitalized interest $ 6,927 $ 12,610 Supplemental non-cash information Investing Increase in accrued property, plant and equipment purchases $ 10,159 $ 2,233 Financing Contributions from an affiliate holding limited partner interests $ — $ 4,000 Accrued distributions on convertible preferred units $ 8,354 $ 8,885 Paid-in-kind distributions on convertible preferred units $ — $ 2,733

Reportable Segments

Reportable Segments	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Reportable Segments	(21) Reportable Segments Our operations are located in the United States and are organized into five reportable segments. These segments have been identified based on the differing products and services, regulatory environments and expertise required for these operations. See Note 3 - Revenue Recognition for a summary of the types of products and services from which each segment derives its revenues. Segment Gross Margin Our Chief Executive Officer serves as our Chief Operating Decision Maker and evaluates the performance of our reportable segments primarily on the basis of segment gross margin, which is our segment measure of profitability. For segments other than Terminalling Services, we define segment gross margin as (i) total revenue plus unconsolidated affiliate earnings less (ii) unrealized gains (losses) on commodity derivatives, construction and operating management agreement income, and the cost of sales. Gross margin for Terminalling Services also deducts direct operating expense which includes direct labor, general materials and supplies and direct overhead. A reconciliation from Total segment gross margin to Net loss attributable to the Partnership for the periods presented is below (in thousands): Three months ended March 31, 2018 2017 Reconciliation of Total Segment Gross Margin to Net loss attributable to the Partnership: Gas Gathering and Processing Services segment gross margin $ 12,653 $ 11,251 Liquid Pipelines and Services segment gross margin 7,271 6,634 Natural Gas Transportation Services segment gross margin 10,688 6,119 Offshore Pipelines and Services segment gross margin 25,316 25,802 Terminalling Services segment gross margin (1) 8,053 11,160 Less: Direct operating expenses (2) 19,124 14,332 Plus: Unrealized gain on commodity derivatives, net 60 365 Less: Corporate expenses 22,692 30,113 Depreciation, amortization and accretion expense 21,997 25,570 Gain on sale of assets, net (95 ) (21 ) Interest expense 13,876 17,956 Other (income) expense (22 ) 37 Other, net 27 392 Income tax expense 280 1,123 Loss from discontinued operations, net of tax — 710 Net income attributable to noncontrolling interests 45 1,303 Net loss attributable to the Partnership $ (13,883 ) $ (30,184 ) _____________________________________ (1) Direct operating expenses related to our Terminalling Services segment of $4.3 million and $3.1 million for the three months ended March 31, 2018 and 2017 , respectively, are included within the calculation of Terminalling Services segment gross margin. (2) Direct operating expenses include Gas Gathering and Processing Services segment direct operating expenses of $6.7 million and $8.1 million , Liquid Pipelines and Services segment direct operating expenses of $3.0 million and $2.5 million , Natural Gas Transportation Services segment direct operating expenses of $1.7 million and $1.2 million and Offshore Pipelines and Services segment direct operating expenses of $7.8 million and $2.6 million for the three months ended March 31, 2018 and 2017 , respectively. The following tables set forth our segment information for the three months ended March 31, 2018 and 2017 (in thousands): Three months ended March 31, 2018 Gas Gathering and Processing Services Liquid Pipelines and Services Natural Gas Transportation Services Offshore Pipelines and Services Terminalling Services Total Revenue $ 35,676 $ 119,773 $ 16,063 $ 16,859 $ 17,398 $ 205,769 Gain (loss) on commodity derivatives, net 2 58 — — — 60 Total revenue 35,678 119,831 16,063 16,859 17,398 205,829 Earnings in unconsolidated affiliates — 2,222 — 10,451 — 12,673 Operating expenses: Cost of Sales 23,056 114,805 5,288 1,994 5,023 150,166 Direct operating expenses 6,680 2,976 1,673 7,795 4,322 23,446 Corporate expenses 22,692 Depreciation, amortization and accretion expense 21,997 Gain on sale of assets, net (95 ) Total operating expenses 218,206 Interest expense 13,876 Other income (22 ) Loss from continuing operations before income taxes (13,558 ) Income tax expense (280 ) Loss from continuing operations (13,838 ) Income from discontinued operations, including gain on disposition — Net loss (13,838 ) Less: Net income attributable to non-controlling interests 45 Net loss attributable to the Partnership $ (13,883 ) Segment gross margin $ 12,653 $ 7,271 $ 10,688 $ 25,316 $ 8,053 Three months ended March 31, 2017 Gas Gathering and Processing Services Liquid Pipelines and Services Natural Gas Transportation Services Offshore Pipelines and Services Terminalling Services Total Revenue $ 34,407 $ 83,411 $ 12,438 $ 14,831 $ 18,626 $ 163,713 Gain (loss) on commodity derivatives, net (7 ) 372 — — — — 365 Total revenue 34,400 83,783 12,438 14,831 18,626 164,078 Earnings in unconsolidated affiliates — 1,088 — 14,314 — 15,402 Operating expenses: Cost of Sales 23,187 78,285 6,260 3,343 4,393 115,468 Direct operating expenses 8,065 2,453 1,235 2,579 3,073 17,405 Corporate expenses 30,113 Depreciation, amortization and accretion expense 25,570 Gain on sale of assets, net (21 ) Total operating expenses 188,535 Interest expense 17,956 Other expense 37 Loss from continuing operations before income taxes (27,048 ) Income tax expense (1,123 ) Loss from continuing operations (28,171 ) Loss from discontinued operations (710 ) Net loss (28,881 ) Less: Net income attributable to non-controlling interests 1,303 Net loss attributable to the Partnership $ (30,184 ) Segment gross margin $ 11,251 $ 6,634 $ 6,119 $ 25,802 $ 11,160 A reconciliation of total assets and investment in equity method investees as of March 31, 2018 and December 31, 2017 by segment to the amounts included in the condensed consolidated balance sheets follows: March 31, December 31, 2018 2017 Segment assets: Gas Gathering and Processing Services $ 400,757 $ 404,872 Liquid Pipelines and Services 379,592 359,646 Offshore Pipelines and Services 537,548 553,213 Natural Gas Transportation Services 267,782 268,991 Terminalling Services 291,662 293,085 Other (1) 55,921 43,659 Total Assets $ 1,933,262 $ 1,923,466 Investment in equity method investees: Liquid Pipelines and Services $ 66,421 $ 64,399 Offshore Pipelines and Services 272,850 284,035 Total Investment in equity method investees $ 339,271 $ 348,434 _____________________________________ (1) Other assets consist primarily of corporate assets not allocable to segments, such as leasehold improvements and other current assets. The following table sets forth capital expenditures for the periods ended March 31, 2018 and 2017 by segment: Three months ended March 31, 2018 2017 (1) Capital expenditures (1) Gas Gathering and Processing Services $ 6,654 $ 4,383 Liquid Pipelines and Services 6,414 370 Offshore Pipelines and Services 6,350 220 Natural Gas Transportation Services 1,338 10,228 Terminalling Services 3,705 1,811 Corporate and other 1,485 2,089 Total Capital expenditures $ 25,946 $ 19,101 _________________________ (1) Capital expenditures for the period ended March 31, 2017 excludes expenditures made for the Propane Business of approximately $1.1 million .

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	(22) Subsequent Events Distribution On April 26, 2018 , we announced that the Board of Directors of our General Partner declared a quarterly cash distribution of $0.4125 per common unit and preferred unit, Series A and Series C, for the quarter ended March 31, 2018 , or $1.65 per common unit on an annualized basis. The distribution was paid on May 15, 2018 , to unitholders of record as of the close of business on May 7, 2018 .

Organization and Basis of Pre31

Organization and Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization American Midstream Partners, LP (together with its consolidated subsidiaries, the “Partnership”, “we”, “us”, or “our”) is a growth-oriented Delaware limited partnership that was formed in August 2009 to own, operate, develop and acquire a diversified portfolio of midstream energy assets. The Partnership’s general partner, American Midstream GP, LLC (the “General Partner”), is 77% directly owned by High Point Infrastructure Partners, LLC (“HPIP”) and 23% indirectly owned by Magnolia Infrastructure Holdings, LLC (“Magnolia”), both of which are affiliates of ArcLight Capital Partners, LLC ("ArcLight"). Our capital accounts consist of notional General Partner units and units representing limited partner interests. We provide critical midstream infrastructure that links producers of natural gas, crude oil, NGLs, condensate and specialty chemicals to numerous intermediate and end-use markets. Through our five reportable segments, (1) gas gathering and processing services, (2) liquid pipelines and services, (3) natural gas transportation services, (4) offshore pipelines and services, and (5) terminalling services, we engage in the business of gathering, treating, processing and transporting natural gas; gathering, transporting, storing, treating and fractionating NGLs; gathering, storing and transporting crude oil and condensates and storing specialty chemical products and refined products. Most of our cash flow is generated from fee-based and fixed-margin compensation for gathering, processing, transporting and treating natural gas and crude oil, firm capacity reservation charges, interruptible transportation charges, guaranteed firm storage contracts, throughput fees and other optional charges associated with ancillary services. Our primary assets are strategically located in some of the most prolific onshore and offshore producing regions and key demand markets in the United States. Our gathering and processing assets are primarily located in (i) the Permian Basin of West Texas, (ii) the Cotton Valley/Haynesville Shale of East Texas, (iii) the Eagle Ford Shale of South Texas, (iv) the Bakken Shale of North Dakota, and (v) offshore in the Gulf of Mexico. Our transmission and terminal assets are in key demand markets in Oklahoma, Alabama, Arkansas, Louisiana, Mississippi and Tennessee and in the Port of New Orleans in Louisiana and the Port of Brunswick in Georgia.
Basis of Presentation	Basis of presentation The accompanying condensed consolidated financial statements have been prepared in accordance with GAAP for interim consolidated financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. They do not include all of the information and notes required by GAAP for annual consolidated financial statements and should therefore be read in conjunction with our annual consolidated financial statements and notes presented in our Annual Report on Form 10-K for the year ended December 31, 2017. In the opinion of management, the condensed consolidated financial statements contain all adjustments, consisting only of normal recurring adjustments, necessary to fairly state our financial position, results of operations and cash flows for the interim periods reported. These condensed consolidated financial statements follow the same significant accounting policies as those included in our annual consolidated financial statements for the year ended December 31, 2017, except for the adoption of new standards. See Notes 2 and 3 for additional information on the adoption of new standards. Certain prior period amounts have been reclassified to conform to the current presentation. The accompanying condensed consolidated financial statements include accounts of the Partnership and its consolidated subsidiaries. All significant inter-company accounts and transactions have been eliminated in the preparation of the accompanying condensed consolidated financial statements. We may enter into transactions with ArcLight or its affiliates whereby we receive midstream assets or other businesses in exchange for cash or Partnership's equity. As the transactions are between entities under common control we account for the net assets acquired at the affiliate's historical cost basis, whether the transactions are considered assets or business acquisitions. In certain cases, our historical financial statements will be revised to include the results attributable to the assets acquired from the later of April 15, 2013 (the date ArcLight affiliates obtained control of our General Partner) or the date the ArcLight affiliates obtained control of the assets or business acquired.
New Accounting Pronouncements	Adopted in 2018 The Partnership adopted Accounting Standards Update (“ASU”) No. 2014-09, “ Revenue from Contracts with Customers (Topic 606) ” issued by the Financial Accounting Standards Board (FASB) on January 1, 2018. See Note 3 - Revenue Recognition for more information on the impact of its adoption . In August 2016, the FASB issued ASU No. 2016-15, “ Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments ” (“ASU 2016-15”). ASU 2016-15 provides specific guidance on eight cash flow classification issues, including debt prepayment or debt extinguishment costs, to reduce diversity in practice. ASU 2016-15 is effective for interim and annual periods beginning after December 15, 2017. There was no impact of the retrospective adoption of this ASU on the Partnership’s condensed consolidated statement of cash flows. In November 2016, the FASB issued ASU No. 2016-18 (“ASU 2016-18”), “ Statement of Cash Flows (Topic 230): Restricted Cash ”, which requires amounts described as restricted cash and restricted cash equivalents to be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. A reconciliation between the balance sheet and the statement of cash flows must be disclosed when the balance sheet includes more than one line item for cash, cash equivalents, restricted cash and restricted cash equivalents. ASU 2016-18 is effective for fiscal years beginning after December 15, 2017. We adopted both ASU 2016-15 and ASU 2016-18 on its effective date of January 1, 2018 using the retrospective transition method. Upon adoption of the standards, the Partnership’s condensed consolidated statement of cash flows for the period ended March 31, 2017 was impacted as follows (in thousands): Three months ended March 31, 2017 Condensed Consolidated Statement of Cash Flows As Previously Reported Effect of Adoption As Adjusted Cash flows from operating activities Net loss $ (28,881 ) $ — $ (28,881 ) Adjustments to reconcile net loss to net cash provided by operating activities including discontinued operations (excluding ‘Other non-cash items’) 39,416 — 39,416 Restricted cash, short-term (3,135 ) 3,135 (1 ) — Changes in operating assets and liabilities, net of effects of assets acquired and liabilities assumed (excluding ‘Restricted cash’) (1,633 ) (55 ) (1 ) (1,688 ) Net cash provided by (used in) operating activities 5,767 3,080 8,847 Cash flows from investing activities Restricted cash 299,313 (299,313 ) (1 ) — Other investing activities (excluding ‘Restricted cash’) (12,928 ) (12,928 ) Net cash provided by (used in) investing activities 286,385 (299,313 ) (12,928 ) Cash flows from financing activities Other financing activities (280,899 ) — (280,899 ) Net cash used in financing activities (280,899 ) — (280,899 ) Net increase (decrease) in cash, cash equivalents, and restricted cash 11,253 (296,233 ) (284,980 ) Cash, cash equivalents and Restricted Cash Beginning of period 5,666 323,564 329,230 End of period $ 16,919 $ 27,331 $ 44,250 _____________________________________________ (1) ASU 2016-18 adjustment to move restricted cash to be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the condensed consolidated statement of cash flows. In May 2017, the FASB issued ASU No. 2017-09, “ Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting ” (“ASU 2017-09”). ASU 2017-09 was issued with the intent to clarify the scope of modification accounting and when it should be applied to a change to the terms or conditions of a share-based payment award. Under the new guidance, modification accounting is required for all changes to share based payment awards, unless all the following conditions are met: (i) there is no change to the fair value of the award, (ii) the vesting conditions have not changed, and iii) the classification of the award as an equity instrument or a debt instrument has not changed. The accounting update was adopted on its effective date January 1, 2018, on a prospective basis. Based on historical patterns of our unit-based awards, which did not involve material modifications, we do not expect the adoption of this accounting update to have a material impact on our consolidated financial position, cash flows or results of operations. In March 2018, the FASB issued ASU No. 2018-05, “ Income Taxes (Topic 740): Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118 (SEC Update) ”, to provide guidance for companies that have not completed their accounting for the income tax effects of the Tax Cuts and Jobs Act (the “Act”) in the period of enactment. The measurement period begins in the reporting period that includes the Act’s enactment date of December 22, 2017, and ends when a company has obtained, prepared and analyzed the information needed to complete the accounting requirements under ASU No. 2018-05/Topic 740 and should not extend beyond one year from the enactment date. The impact of adopting the new guidance on our consolidated financial position, cash flows or results of operations, as well as on related disclosures was immaterial. Standards Not Yet Adopted In February 2016, the FASB issued ASU No. 2016-02 (Topic 842) " Leases ", which supersedes the lease recognition requirements in Accounting Standards Codification (“ASC”) Topic 840, "Leases" . Under ASU No. 2016-02, lessees are required to recognize assets and liabilities on the balance sheet for most leases and to provide enhanced disclosures. Leases will continue to be classified as either finance or operating. ASU No. 2016-02 is effective for annual reporting periods, and interim periods within those years beginning after December 15, 2018. Entities are required to use a modified retrospective approach for leases that exist or are entered into after the beginning of the earliest comparative period in the financial statements, and there are certain optional practical expedients that an entity may elect to apply. Full retrospective application is prohibited, and early adoption by public entities is permitted. We are in the process of evaluating the impact of ASU No. 2016-02 on our consolidated financial statements as we will be required to reflect our various lease obligations and associated asset use rights on our consolidated balance sheets. The adoption may also impact our debt covenant compliance and may require us to modify or replace certain of our existing information systems. We are finalizing our selection of a third-party consulting firm to assist us with the adoption of the new guidance and are currently in the Impact Assessment phase. We are not yet able to determine whether the adoption of this standard will have a material impact on our consolidated financial statements and related disclosures, including additional changes, if any, to our accounting system to capture data for disclosure purposes. We will adopt the guidance on its effective date January 1, 2019. In January 2018, the FASB issued ASU No. 2018-01, “ Leases - Land Easement Practical Expedient for Transition to Topic 842 ” to provide an optional transition practical expedient to forego evaluation under Topic 842 of existing or expired land easements that were not previously accounted for as leases under the current guidance found in Topic 840. An entity that elects this practical expedient should evaluate new or modified land easements under Topic 842 beginning at the date that the entity adopts Topic 842. An entity that does not elect this practical expedient should evaluate all existing or expired land easements in connection with the adoption of the new lease requirements in Topic 842 to assess whether they meet the definition of a lease. As discussed above, we are finalizing our selection of a third-party consulting firm to assist us with the adoption of the new guidance and are currently in the Impact Assessment phase. We are not yet able to determine whether we would elect this practical expedient or whether the adoption of this standard will have a material impact on our consolidated financial position, results of operations and cash flows, as well as related disclosures, including additional changes, if any, to our accounting system to capture data for disclosure purposes. We will adopt this on its effective date January 1, 2019. In June 2016, the FASB issued ASU 2016-13, “ Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” . This guidance will become effective for interim and annual periods beginning after December 15, 2019. We expect to adopt this ASU on January 1, 2020, and we are currently evaluating the effect that adopting this guidance will have on our consolidated financial position, results of operations and cash flows.

New Accounting Pronouncements (

New Accounting Pronouncements (Tables)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Impact of New Accounting Pronouncements	We adopted both ASU 2016-15 and ASU 2016-18 on its effective date of January 1, 2018 using the retrospective transition method. Upon adoption of the standards, the Partnership’s condensed consolidated statement of cash flows for the period ended March 31, 2017 was impacted as follows (in thousands): Three months ended March 31, 2017 Condensed Consolidated Statement of Cash Flows As Previously Reported Effect of Adoption As Adjusted Cash flows from operating activities Net loss $ (28,881 ) $ — $ (28,881 ) Adjustments to reconcile net loss to net cash provided by operating activities including discontinued operations (excluding ‘Other non-cash items’) 39,416 — 39,416 Restricted cash, short-term (3,135 ) 3,135 (1 ) — Changes in operating assets and liabilities, net of effects of assets acquired and liabilities assumed (excluding ‘Restricted cash’) (1,633 ) (55 ) (1 ) (1,688 ) Net cash provided by (used in) operating activities 5,767 3,080 8,847 Cash flows from investing activities Restricted cash 299,313 (299,313 ) (1 ) — Other investing activities (excluding ‘Restricted cash’) (12,928 ) (12,928 ) Net cash provided by (used in) investing activities 286,385 (299,313 ) (12,928 ) Cash flows from financing activities Other financing activities (280,899 ) — (280,899 ) Net cash used in financing activities (280,899 ) — (280,899 ) Net increase (decrease) in cash, cash equivalents, and restricted cash 11,253 (296,233 ) (284,980 ) Cash, cash equivalents and Restricted Cash Beginning of period 5,666 323,564 329,230 End of period $ 16,919 $ 27,331 $ 44,250 _____________________________________________ (1) ASU 2016-18 adjustment to move restricted cash to be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the condensed consolidated statement of cash flows. The following tables summarize the impacts of adopting Topic 606 on the Partnership’s condensed consolidated financial statements as of and for the three months ended March 31, 2018, adjusting for the differences between revenue as reported following adoption of Topic 606 and revenue as it would have been reported under previous standards (in thousands): Three months ended March 31, 2018 Condensed Consolidated Statement of Income As Reported Adjustments Amounts without Adoption of Topic 606 Revenue Commodity sales $ 158,863 $ 5,242 $ 164,105 Services 46,906 (2,681 ) 44,225 Operating expenses Costs of sales 150,166 3,165 153,331 Direct operating expenses 23,446 (456 ) 22,990 Operating loss (12,377 ) (148 ) (12,525 ) Net loss attributable to the Partnership $ (13,883 ) $ (148 ) $ (14,031 ) General Partner’s interest in net loss $ (181 ) $ (2 ) $ (183 ) Limited Partners’ interest in net loss (13,702 ) (146 ) (13,848 ) As of March 31, 2018 Condensed Consolidated Balance Sheet (in thousands) As Reported Adjustments Amounts without Adoption of Topic 606 Assets Accounts receivable, net $ 87,418 $ (67,553 ) $ 19,865 Unbilled revenue — 67,553 67,553 Other current assets 25,265 — 25,265 Other noncurrent assets 25,249 (3,419 ) 21,830 Liabilities Accrued expenses and other current liabilities 88,123 — 88,123 Liabilities held for sale 3,337 (459 ) 2,878 Other noncurrent liabilities 15,542 (13,503 ) 2,039 Equity and partners’ capital General partner interests $ (88,746 ) $ 137 $ (88,609 ) Limited partner interests 221,346 10,406 231,752

Revenue Recognition (Tables)

Revenue Recognition (Tables)	3 Months Ended
	Mar. 31, 2018
Revenue from Contract with Customer [Abstract]
Impact of New Accounting Pronouncements	We adopted both ASU 2016-15 and ASU 2016-18 on its effective date of January 1, 2018 using the retrospective transition method. Upon adoption of the standards, the Partnership’s condensed consolidated statement of cash flows for the period ended March 31, 2017 was impacted as follows (in thousands): Three months ended March 31, 2017 Condensed Consolidated Statement of Cash Flows As Previously Reported Effect of Adoption As Adjusted Cash flows from operating activities Net loss $ (28,881 ) $ — $ (28,881 ) Adjustments to reconcile net loss to net cash provided by operating activities including discontinued operations (excluding ‘Other non-cash items’) 39,416 — 39,416 Restricted cash, short-term (3,135 ) 3,135 (1 ) — Changes in operating assets and liabilities, net of effects of assets acquired and liabilities assumed (excluding ‘Restricted cash’) (1,633 ) (55 ) (1 ) (1,688 ) Net cash provided by (used in) operating activities 5,767 3,080 8,847 Cash flows from investing activities Restricted cash 299,313 (299,313 ) (1 ) — Other investing activities (excluding ‘Restricted cash’) (12,928 ) (12,928 ) Net cash provided by (used in) investing activities 286,385 (299,313 ) (12,928 ) Cash flows from financing activities Other financing activities (280,899 ) — (280,899 ) Net cash used in financing activities (280,899 ) — (280,899 ) Net increase (decrease) in cash, cash equivalents, and restricted cash 11,253 (296,233 ) (284,980 ) Cash, cash equivalents and Restricted Cash Beginning of period 5,666 323,564 329,230 End of period $ 16,919 $ 27,331 $ 44,250 _____________________________________________ (1) ASU 2016-18 adjustment to move restricted cash to be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the condensed consolidated statement of cash flows. The following tables summarize the impacts of adopting Topic 606 on the Partnership’s condensed consolidated financial statements as of and for the three months ended March 31, 2018, adjusting for the differences between revenue as reported following adoption of Topic 606 and revenue as it would have been reported under previous standards (in thousands): Three months ended March 31, 2018 Condensed Consolidated Statement of Income As Reported Adjustments Amounts without Adoption of Topic 606 Revenue Commodity sales $ 158,863 $ 5,242 $ 164,105 Services 46,906 (2,681 ) 44,225 Operating expenses Costs of sales 150,166 3,165 153,331 Direct operating expenses 23,446 (456 ) 22,990 Operating loss (12,377 ) (148 ) (12,525 ) Net loss attributable to the Partnership $ (13,883 ) $ (148 ) $ (14,031 ) General Partner’s interest in net loss $ (181 ) $ (2 ) $ (183 ) Limited Partners’ interest in net loss (13,702 ) (146 ) (13,848 ) As of March 31, 2018 Condensed Consolidated Balance Sheet (in thousands) As Reported Adjustments Amounts without Adoption of Topic 606 Assets Accounts receivable, net $ 87,418 $ (67,553 ) $ 19,865 Unbilled revenue — 67,553 67,553 Other current assets 25,265 — 25,265 Other noncurrent assets 25,249 (3,419 ) 21,830 Liabilities Accrued expenses and other current liabilities 88,123 — 88,123 Liabilities held for sale 3,337 (459 ) 2,878 Other noncurrent liabilities 15,542 (13,503 ) 2,039 Equity and partners’ capital General partner interests $ (88,746 ) $ 137 $ (88,609 ) Limited partner interests 221,346 10,406 231,752
Disaggregation of Revenue	The following table presents the reconciliation of our revenues from contracts with customers to segment revenues and total revenues as disclosed in our condensed consolidated statement of operations (in thousands): Three months ended March 31, 2018 Gas Gathering and Processing Services Liquid Pipelines and Services Natural Gas Transportation Services Offshore Pipelines and Services Terminalling Services Total Revenues from contracts with customers $ 35,676 $ 119,773 $ 16,063 $ 16,859 $ 17,398 $ 205,769 Gains (losses) on commodity derivatives, net 2 58 — — — 60 Total revenues of reportable segments $ 35,678 $ 119,831 $ 16,063 $ 16,859 $ 17,398 $ 205,829 The following table presents our segment revenues from contracts with customers disaggregated by type of activity (in thousands): Three months ended March 31, 2018 Gas Gathering and Processing Services Liquid Pipelines and Services Natural Gas Transportation Services Offshore Pipelines and Services Terminalling Services Total Commodity sales: Natural gas $ 1,906 $ — $ 6,637 $ 2,437 $ — $ 10,980 NGLs 21,150 — — 38 — 21,188 Condensate 5,648 — — 34 — 5,682 Crude oil — 115,782 — — — 115,782 Other sales (1) 183 — 4 40 5,004 5,231 Services: Gathering and processing 6,250 — — 866 — 7,116 Transportation 105 3,588 9,412 8,661 — 21,766 Terminalling and storage — — — — 11,833 11,833 Other services (2) 434 403 10 4,783 561 6,191 Revenues from contracts with customers $ 35,676 $ 119,773 $ 16,063 $ 16,859 $ 17,398 $ 205,769 (1) Other commodity sales for our Terminalling Services segment include sales of refined product. The Partnership is actively marketing for sale all of its assets in the Terminalling Services segment. See Note 4 - Acquisitions and Dispositions. (2) Other services in our Offshore Pipelines and Services segment include asset management services.
Contract Balances	The following table presents the change in the contract assets and liability balances during the three months ended March 31, 2018 (in thousands): Contract Assets Contract Liabilities Balance at December 31, 2017 $ — $ 2,136 Topic 606 implementation 2,555 13,246 Amounts recognized as revenue — (502 ) Additions 864 1,205 Total balance at March 31, 2018 3,419 16,085 Classified as held for sale — (708 ) Balance at March 31, 2018 $ 3,419 $ 15,377 Current — 998 Noncurrent 3,419 14,379 Balance at March 31, 2018 $ 3,419 $ 15,377 Trade accounts receivable, net consists of the following as presented on our condensed consolidated balance sheet (in thousands): March 31, 2018 Receivables arising from revenue contracts Unbilled customer receivables $ 67,553 Billed customer receivables 20,177 Allowance for doubtful accounts (312 ) Accounts receivable, net $ 87,418
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction	Therefore, the following table as of March 31, 2018, represents only revenue expected to be recognized from contracts where the price and quantity of the product or service are fixed: Remainder of 2018 2019 2020 2021 2022 Thereafter Total Gathering and processing revenues supported by minimum volume commitments $ 9,252 $ 12,743 $ 12,743 $ 12,720 $ 12,467 $ 19,155 $ 79,080 Transportation agreements 15,921 19,233 18,475 18,207 18,100 190,416 280,352 Terminalling and storage throughput agreements 10,821 12,823 6,220 2,715 1,593 — 34,172 Other 1,170 1,560 1,560 — — — 4,290 Total $ 37,164 $ 46,359 $ 38,998 $ 33,642 $ 32,160 $ 209,571 $ 397,894

Acquisitions and Dispositions (

Acquisitions and Dispositions (Tables)	3 Months Ended
	Mar. 31, 2018
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	March 31, 2018 Accounts receivable, net $ 3,376 Inventory 1,571 Other current assets 893 Property, plant and equipment, net 32,129 Goodwill 61,163 Intangible assets 29,403 Other non-current assets 712 Total assets held for sale $ 129,247 Accounts payable $ 1,219 Accrued gas purchases 630 Accrued expenses and other current liabilities 881 Contract liabilities, long-term 607 Total liabilities held for sale $ 3,337 The Partnership has reported the accounts and the results of our Propane Business as discontinued operations in our condensed consolidated statements of operations for the three months ended March 31, 2017. Summarized financial information related to the Propane Business is set forth in the tables below (in thousands): Three months ended March 31, 2017 Total revenue $ 35,554 Total operating expenses 36,305 Operating loss (751 ) Other income 41 Income tax expense — Loss from discontinued operations before taxes $ (710 ) Partnership’s loss from discontinued operations, net of tax $ (710 ) Depreciation and amortization $ 3,781 Capital expenditures $ 1,119 Operating non-cash items Unrealized gain loss on derivative contracts, net $ 901

Inventory (Tables)

Inventory (Tables)	3 Months Ended
	Mar. 31, 2018
Inventory Disclosure [Abstract]
Schedule of Inventory	Inventory consists of the following (in thousands): March 31, 2018 December 31, 2017 Crude oil $ 4,378 $ 1,553 NGLs 282 347 Refined products — 934 Materials, supplies and equipment 135 132 Total inventory $ 4,795 $ 2,966

Other Current Assets (Tables)

Other Current Assets (Tables)	3 Months Ended
	Mar. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Schedule of Other Current Assets	Other current assets consist of the following (in thousands): March 31, 2018 December 31, 2017 Prepaid insurance $ 6,341 $ 8,944 Insurance receivables 1,741 1,741 Due from related parties 5,427 4,362 Other receivables 6,393 5,187 Risk management assets 5,363 3,186 Total other current assets $ 25,265 $ 23,420

Risk Management Activities (Tab

Risk Management Activities (Tables)	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of notional amounts of outstanding derivative positions	The following table summarizes the net notional volumes of our outstanding commodity-related derivatives, excluding those contracts that qualified for the NPNS exception as of March 31, 2018 and December 31, 2017, none of which were designated as hedges for accounting purposes. March 31, 2018 December 31, 2017 Commodity Swaps Volume Maturity Volume Maturity NGLs Fixed Price (gallons) 1,407,000 January 2019 — — Crude Oil Fixed Price (barrels) 17,000 April 2018 — —
Fair value associated with commodity derivative instruments	The following table summarizes the fair values of our derivative contracts (before netting adjustments) included in the condensed consolidated balance sheets (in thousands): Asset Derivatives Liability Derivatives Type Balance Sheet Classification March 31, December 31, 2017 March 31, December 31, 2017 Commodity derivatives Other current assets $ 5 $ — $ — $ — Commodity derivatives Accrued expenses and other current liabilities — — (64 ) — Interest rate swaps Other current assets $ 5,132 $ 2,678 $ — $ — Interest rate swaps Other assets net 11,524 8,807 — — Weather derivatives Other current assets $ 231 $ 509 $ — $ — Total $ 16,892 $ 11,994 $ (64 ) $ — The following tables present the fair value of our recognized derivative assets and liabilities on a gross basis and amounts offset in the condensed consolidated balance sheets that are subject to enforceable master netting arrangements (in thousands): Gross Risk Management Position Netting Adjustments Net Risk Management Position Balance Sheet Classification March 31, December 31, 2017 March 31, December 31, 2017 March 31, December 31, 2017 Other current assets $ 5,368 $ 3,187 $ (5 ) $ — $ 5,363 $ 3,187 Other (noncurrent) assets, net 11,524 8,807 — — 11,524 8,807 Total assets $ 16,892 $ 11,994 $ (5 ) $ — $ 16,887 $ 11,994 Accrued expenses and other current liabilities $ (64 ) $ — $ 5 $ — $ (59 ) $ — Total liabilities $ (64 ) $ — $ 5 $ — $ (59 ) $ —
Realized and unrealized gains (losses) with commodity and interest rate derivative instruments	For each of the three months ended March 31, 2018 and 2017 , the realized and unrealized gains (losses) associated with our commodity, interest rate and weather derivative instruments were recorded in our condensed consolidated statements of operations as follows (in thousands): Three months ended March 31, Statement of Operations Classification Realized Unrealized 2018 Gains (losses) on commodity derivatives, net $ 119 $ (59 ) Interest expense 1,350 5,171 Direct operating expenses (278 ) — Total $ 1,191 $ 5,112 2017 Gains (losses) on commodity derivatives, net $ 420 $ (55 ) Interest expense (65 ) (317 ) Direct operating expenses (257 ) — Total $ 98 $ (372 )

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	3 Months Ended
	Mar. 31, 2018
Property, Plant and Equipment [Abstract]
Property, plant and equipment	Property, plant and equipment, net, consists of the following (in thousands): Useful Life (in years) March 31, December 31, Land Infinite $ 16,366 $ 18,145 Construction in progress N/A 83,013 55,622 Buildings and improvements 4 to 40 15,476 16,235 Transportation equipment 5 to 15 22,597 22,697 Processing and treating plants 8 to 40 123,580 123,138 Pipelines, compressors and right-of-way 3 to 40 975,213 974,301 Storage 3 to 40 124,037 146,105 Equipment 3 to 31 61,935 80,220 Total property, plant and equipment 1,422,217 1,436,463 Accumulated depreciation (341,320 ) (340,878 ) Property, plant and equipment, net $ 1,080,897 $ 1,095,585

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Goodwill consists of the following (in thousands): March 31, 2018 December 31, 2017 Liquid Pipelines and Services $ 35,710 $ 35,708 Terminalling Services 27,303 88,466 Offshore Pipeline and Services 4,972 4,692 Total $ 67,985 $ 128,866
Schedule of Finite-Lived Intangible Assets	Intangible assets, net, consist of the following (in thousands): March 31, 2018 Gross carrying amount Accumulated amortization Net carrying amount Customer relationships $ 64,744 $ (14,806 ) $ 49,938 Customer contracts 94,692 (49,420 ) 45,272 Dedicated acreage 42,547 (6,560 ) 35,987 Collaborative arrangements 11,884 (1,627 ) 10,257 Noncompete agreements 1,064 (1,064 ) — Other 198 (25 ) 173 Total $ 215,129 $ (73,502 ) $ 141,627 December 31, 2017 Gross carrying amount Accumulated amortization Net carrying amount Customer relationships $ 110,483 $ (29,965 ) $ 80,518 Customer contracts 94,692 (48,173 ) 46,519 Dedicated acreage 42,547 (6,216 ) 36,331 Collaborative arrangements 11,884 (1,415 ) 10,469 Noncompete agreements 1,064 (1,064 ) — Other 198 (25 ) 173 Total $ 260,868 $ (86,858 ) $ 174,010

Investment in Unconsolidated 40

Investment in Unconsolidated Affiliates (Tables)	3 Months Ended
	Mar. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Investments in and Advances to Affiliates	The following table presents the activity in our equity method investments in unconsolidated affiliates (in thousands): Delta House (1) Emerald Transactions FPS (3) OGL (3) Destin (3) Tri-States (2) Okeanos (3) Wilprise (2) Cayenne JV (2) Total Ownership % - 12/31/2017 35.7 % 35.7 % 66.7 % 16.7 % 66.7 % 25.3% 50.0 % Ownership % - 3/31/2018 35.7 % 35.7 % 66.7 % 16.7 % 66.7 % 25.3% 50.0 % Balances at December 31, 2017 $ 90,412 $ 46,932 $ 124,245 $ 53,057 $ 22,445 $ 4,689 $ 6,654 $ 348,434 Earnings in unconsolidated affiliates 3,227 2,715 2,377 854 2,132 258 1,110 12,673 Contributions — — — — — — 2,018 2,018 Distributions (2,247 ) (4,278 ) (10,734 ) (2,034 ) (4,378 ) (183 ) — (23,854 ) Balances at March 31, 2018 $ 91,392 $ 45,369 $ 115,888 $ 51,877 $ 20,199 $ 4,764 $ 9,782 $ 339,271 ___________________________________________________ (1) Represents direct and indirect ownership interests in Class A units and common units. FPS denotes Floating Production System LLC whereas OGL denotes Oil & Gas Lateral LLC. (2) Included in our Liquid Pipelines and Services segment. (3) Included in our Offshore Pipelines and Services segment.
Equity Method Investments	The following tables present the summarized combined financial information for our equity investments (amounts represent 100% of investee financial information) (in thousands): Balance Sheets: March 31, 2018 December 31, 2017 Current assets $ 64,381 $ 80,405 Non-current assets 1,279,417 1,288,862 Current liabilities 114,724 130,904 Non-current liabilities $ 438,496 $ 436,584 Three months ended March 31, Statements of Operations: 2018 2017 Revenue $ 56,898 $ 93,870 Operating expenses 6,292 8,436 Net income $ 32,845 $ 69,285

Accrued Expenses and Other Cu41

Accrued Expenses and Other Current Liabilities (Tables)	3 Months Ended
	Mar. 31, 2018
Other Liabilities Disclosure [Abstract]
Schedule of Accrued Liabilities	Accrued expenses and other current liabilities consists of the following (in thousands): March 31, 2018 December 31, 2017 Capital expenditures $ 20,880 $ 10,721 Accrued interest 15,590 3,190 Convertible preferred unit distributions 8,354 — Employee compensation 149 90 Current portion of asset retirement obligation 6,416 6,416 Additional Blackwater acquisition consideration 5,000 5,000 Transaction costs 3,732 3,408 Customer deposits 1,136 1,109 Taxes payable 4,018 5,263 Due to related parties 3,212 6,609 Deferred financing costs — 266 Contingent liabilities associated with VKGS and Panther 2,098 2,099 Royalties, gas imbalance and leases payables 7,119 7,905 Professional fees 2,024 1,848 Accrued corporate expenses 1,697 2,487 Accrued operating expenses 4,881 6,609 Other 1,817 5,834 Total accrued expenses and other current liabilities $ 88,123 $ 68,854

Asset Retirement Obligations (T

Asset Retirement Obligations (Tables)	3 Months Ended
	Mar. 31, 2018
Asset Retirement Obligation Disclosure [Abstract]
Schedule of Change in Asset Retirement Obligation	The following table presents activity in our asset retirement obligations for the three months ended March 31, 2018 (in thousands): Non-current balance $ 66,194 Current balance 6,416 Balances at December 31, 2017 $ 72,610 Additions 260 Expenditures — Accretion expense 440 Balances at March 31, 2018 $ 73,310 Less: current portion 6,416 Noncurrent asset retirement obligation $ 66,894

Debt Obligations (Tables)

Debt Obligations (Tables)	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Outstanding borrowings under the credit facility	Our outstanding debt consists of the following (in thousands): March 31, 2018 December 31, 2017 Revolving credit facility $ 712,600 $ 697,900 8.50% Senior unsecured notes, due 2021 425,000 425,000 3.77% Senior secured notes, due 2031 (non-recourse) 57,817 58,324 3.97% Senior secured notes, due 2032 (non-recourse) 31,586 32,025 Other debt (1) 2,431 4,989 Total debt obligations 1,229,434 1,218,238 Unamortized debt issuance costs (2) (9,530 ) (9,231 ) Total debt 1,219,904 1,209,007 Less: Current portion, including unamortized debt issuance costs (5,058 ) (7,551 ) Long term debt $ 1,214,846 $ 1,201,456 ___________________________ (1) Other debt includes miscellaneous long-term obligations, which are reported in Other liabilities line items on our condensed consolidated balance sheets. (2) Unamortized debt issuance costs related to the revolving credit facility are included in our condensed consolidated balance sheets in Other assets, net.
Schedule of redemption percentages	On and after December 15, 2018, the Issuers may redeem all or a part of the 8.50% Senior Notes, at the redemption prices (expressed as percentages of principal amount) set forth below, plus accrued and unpaid interest, if redeemed during the twelve-month period beginning on December 15 of the years indicated below: Year Percentage 2018 104.250% 2019 102.125% 2020 and thereafter 100.000%

Convertible Preferred Units (Ta

Convertible Preferred Units (Tables)	3 Months Ended
	Mar. 31, 2018
Partners' Capital [Abstract]
Schedule of Preferred Units	Our convertible preferred units consist of the following (in thousands): Series A Series C Total Units $ Units $ $ December 31, 2017 10,719 $ 191,798 8,965 $ 125,382 $ 317,180 Paid in kind unit distributions 291 — 277 — — March 31, 2018 11,010 $ 191,798 9,242 $ 125,382 $ 317,180

Partners Capital (Tables)

Partners Capital (Tables)	3 Months Ended
	Mar. 31, 2018
Equity [Abstract]
Schedule of Units Outstanding and Distributions	The following table presents unit activity (in thousands): General Limited Partner Interest Balances at December 31, 2017 965 52,711 LTIP vesting — 142 Balances at March 31, 2018 965 52,853 We made the following distributions (in thousands): Three months ended March 31, 2018 2017 Series A Units Cash Paid $ — $ 2,527 Accrued (1) 4,542 4,296 Paid-in-kind units — 2,733 Series C Units Cash Paid — 3,627 Accrued (1) 3,812 3,627 Paid-in-kind units — — Series D Units Cash Paid — 962 Accrued — 962 Limited Partner Units Cash Paid 21,745 24,915 General Partner Units Cash Paid 290 167 Summary Cash Paid 22,035 32,198 Accrued (1) 8,354 8,885 Paid-in-kind units — 2,733 (1) Can include either Cash, PIK or a combination of both.

Net Loss per Limited Partner 46

Net Loss per Limited Partner Unit (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Schedule of Calculation for Net Loss Per Limited Partner Unit	The calculation of basic and diluted limited partners' net loss per common unit is summarized below (in thousands, except per unit amounts): Three months ended March 31, 2018 2017 Loss from continuing operations $ (13,838 ) $ (28,171 ) Less: Net income attributable to noncontrolling interests 45 1,303 Loss attributable to the Partnership (13,883 ) (29,474 ) Less: Distributions on Series A Units 4,542 4,296 Distributions on Series C Units 3,812 3,627 Distributions on Series D Units — 962 General Partner's distribution 290 200 General Partner's share in undistributed loss (583 ) (560 ) Loss attributable to Limited Partners (21,944 ) (37,999 ) Loss from discontinued operations, net of tax — (710 ) Net loss attributable to Limited Partners $ (21,944 ) $ (38,709 ) Weighted average number of common units outstanding - Basic and Diluted 52,769 51,451 Limited Partners' net loss per common unit - Basic and Diluted Loss from continuing operations $ (0.42 ) $ (0.74 ) Loss from discontinued operations — (0.01 ) Net loss (1) $ (0.42 ) $ (0.75 ) _____________________________________ (1) Potential common unit equivalents are antidilutive for all periods presented and, as a result, have been excluded from the determination of diluted limited partners' net loss per common unit.

Supplemental Cash Flow Inform47

Supplemental Cash Flow Information (Tables)	3 Months Ended
	Mar. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Schedule of Supplemental Cash Flow Information	Supplemental cash flows and non-cash transactions consist of the following (in thousands): Three months ended March 31, 2018 2017 Supplemental cash flow information Interest payments, net of capitalized interest $ 6,927 $ 12,610 Supplemental non-cash information Investing Increase in accrued property, plant and equipment purchases $ 10,159 $ 2,233 Financing Contributions from an affiliate holding limited partner interests $ — $ 4,000 Accrued distributions on convertible preferred units $ 8,354 $ 8,885 Paid-in-kind distributions on convertible preferred units $ — $ 2,733

Reportable Segments (Tables)

Reportable Segments (Tables)	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Segment information	A reconciliation from Total segment gross margin to Net loss attributable to the Partnership for the periods presented is below (in thousands): Three months ended March 31, 2018 2017 Reconciliation of Total Segment Gross Margin to Net loss attributable to the Partnership: Gas Gathering and Processing Services segment gross margin $ 12,653 $ 11,251 Liquid Pipelines and Services segment gross margin 7,271 6,634 Natural Gas Transportation Services segment gross margin 10,688 6,119 Offshore Pipelines and Services segment gross margin 25,316 25,802 Terminalling Services segment gross margin (1) 8,053 11,160 Less: Direct operating expenses (2) 19,124 14,332 Plus: Unrealized gain on commodity derivatives, net 60 365 Less: Corporate expenses 22,692 30,113 Depreciation, amortization and accretion expense 21,997 25,570 Gain on sale of assets, net (95 ) (21 ) Interest expense 13,876 17,956 Other (income) expense (22 ) 37 Other, net 27 392 Income tax expense 280 1,123 Loss from discontinued operations, net of tax — 710 Net income attributable to noncontrolling interests 45 1,303 Net loss attributable to the Partnership $ (13,883 ) $ (30,184 ) _____________________________________ (1) Direct operating expenses related to our Terminalling Services segment of $4.3 million and $3.1 million for the three months ended March 31, 2018 and 2017 , respectively, are included within the calculation of Terminalling Services segment gross margin. (2) Direct operating expenses include Gas Gathering and Processing Services segment direct operating expenses of $6.7 million and $8.1 million , Liquid Pipelines and Services segment direct operating expenses of $3.0 million and $2.5 million , Natural Gas Transportation Services segment direct operating expenses of $1.7 million and $1.2 million and Offshore Pipelines and Services segment direct operating expenses of $7.8 million and $2.6 million for the three months ended March 31, 2018 and 2017 , respectively. The following tables set forth our segment information for the three months ended March 31, 2018 and 2017 (in thousands): Three months ended March 31, 2018 Gas Gathering and Processing Services Liquid Pipelines and Services Natural Gas Transportation Services Offshore Pipelines and Services Terminalling Services Total Revenue $ 35,676 $ 119,773 $ 16,063 $ 16,859 $ 17,398 $ 205,769 Gain (loss) on commodity derivatives, net 2 58 — — — 60 Total revenue 35,678 119,831 16,063 16,859 17,398 205,829 Earnings in unconsolidated affiliates — 2,222 — 10,451 — 12,673 Operating expenses: Cost of Sales 23,056 114,805 5,288 1,994 5,023 150,166 Direct operating expenses 6,680 2,976 1,673 7,795 4,322 23,446 Corporate expenses 22,692 Depreciation, amortization and accretion expense 21,997 Gain on sale of assets, net (95 ) Total operating expenses 218,206 Interest expense 13,876 Other income (22 ) Loss from continuing operations before income taxes (13,558 ) Income tax expense (280 ) Loss from continuing operations (13,838 ) Income from discontinued operations, including gain on disposition — Net loss (13,838 ) Less: Net income attributable to non-controlling interests 45 Net loss attributable to the Partnership $ (13,883 ) Segment gross margin $ 12,653 $ 7,271 $ 10,688 $ 25,316 $ 8,053 Three months ended March 31, 2017 Gas Gathering and Processing Services Liquid Pipelines and Services Natural Gas Transportation Services Offshore Pipelines and Services Terminalling Services Total Revenue $ 34,407 $ 83,411 $ 12,438 $ 14,831 $ 18,626 $ 163,713 Gain (loss) on commodity derivatives, net (7 ) 372 — — — — 365 Total revenue 34,400 83,783 12,438 14,831 18,626 164,078 Earnings in unconsolidated affiliates — 1,088 — 14,314 — 15,402 Operating expenses: Cost of Sales 23,187 78,285 6,260 3,343 4,393 115,468 Direct operating expenses 8,065 2,453 1,235 2,579 3,073 17,405 Corporate expenses 30,113 Depreciation, amortization and accretion expense 25,570 Gain on sale of assets, net (21 ) Total operating expenses 188,535 Interest expense 17,956 Other expense 37 Loss from continuing operations before income taxes (27,048 ) Income tax expense (1,123 ) Loss from continuing operations (28,171 ) Loss from discontinued operations (710 ) Net loss (28,881 ) Less: Net income attributable to non-controlling interests 1,303 Net loss attributable to the Partnership $ (30,184 ) Segment gross margin $ 11,251 $ 6,634 $ 6,119 $ 25,802 $ 11,160 A reconciliation of total assets and investment in equity method investees as of March 31, 2018 and December 31, 2017 by segment to the amounts included in the condensed consolidated balance sheets follows: March 31, December 31, 2018 2017 Segment assets: Gas Gathering and Processing Services $ 400,757 $ 404,872 Liquid Pipelines and Services 379,592 359,646 Offshore Pipelines and Services 537,548 553,213 Natural Gas Transportation Services 267,782 268,991 Terminalling Services 291,662 293,085 Other (1) 55,921 43,659 Total Assets $ 1,933,262 $ 1,923,466 Investment in equity method investees: Liquid Pipelines and Services $ 66,421 $ 64,399 Offshore Pipelines and Services 272,850 284,035 Total Investment in equity method investees $ 339,271 $ 348,434 _____________________________________ (1) Other assets consist primarily of corporate assets not allocable to segments, such as leasehold improvements and other current assets. The following table sets forth capital expenditures for the periods ended March 31, 2018 and 2017 by segment: Three months ended March 31, 2018 2017 (1) Capital expenditures (1) Gas Gathering and Processing Services $ 6,654 $ 4,383 Liquid Pipelines and Services 6,414 370 Offshore Pipelines and Services 6,350 220 Natural Gas Transportation Services 1,338 10,228 Terminalling Services 3,705 1,811 Corporate and other 1,485 2,089 Total Capital expenditures $ 25,946 $ 19,101 _________________________ (1) Capital expenditures for the period ended March 31, 2017 excludes expenditures made for the Propane Business of approximately $1.1 million .

Organization and Basis of Pre49

Organization and Basis of Presentation (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2018segments	Dec. 31, 2017segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General partners' capital account, percentage		77.00%
Limited partners' capital account, percentage		23.00%
Number of reportable segments	5	5

New Accounting Pronouncements -

New Accounting Pronouncements - Effect of Adoption of New Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net income (loss)	$ (13,838)	$ (28,881)
Adjustments to reconcile net loss to net cash provided by operating activities including discontinued operations (excluding ‘Other non-cash items’)		39,416
Restricted cash, short-term		0
Changes in operating assets and liabilities, net of effects of assets acquired and liabilities assumed (excluding ‘Restricted cash’)		(1,688)
Net cash provided by operating activities	14,847	8,847
Restricted cash		0
Other investing activities (excluding ‘Restricted cash’)		(12,928)
Net cash used in investing activities	(15,744)	(12,928)
Other		(280,899)
Net cash used in financing activities	(1,774)	(280,899)
Net decrease in cash, cash equivalents, and restricted cash	(2,671)	(284,980)
Beginning of period	34,179	329,230
End of period	$ 31,508	44,250
As Previously Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net income (loss)		(28,881)
Adjustments to reconcile net loss to net cash provided by operating activities including discontinued operations (excluding ‘Other non-cash items’)		39,416
Restricted cash, short-term		(3,135)
Changes in operating assets and liabilities, net of effects of assets acquired and liabilities assumed (excluding ‘Restricted cash’)		(1,633)
Net cash provided by operating activities		5,767
Restricted cash		299,313
Other investing activities (excluding ‘Restricted cash’)		(12,928)
Net cash used in investing activities		286,385
Other		(280,899)
Net cash used in financing activities		(280,899)
Net decrease in cash, cash equivalents, and restricted cash		11,253
Beginning of period		5,666
End of period		16,919
ASU 2016-15 and ASU 2016-15 | Effect of Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net income (loss)		0
Adjustments to reconcile net loss to net cash provided by operating activities including discontinued operations (excluding ‘Other non-cash items’)		0
Restricted cash, short-term		3,135
Changes in operating assets and liabilities, net of effects of assets acquired and liabilities assumed (excluding ‘Restricted cash’)		(55)
Net cash provided by operating activities		3,080
Restricted cash		(299,313)
Net cash used in investing activities		(299,313)
Other		0
Net cash used in financing activities		0
Net decrease in cash, cash equivalents, and restricted cash		(296,233)
Beginning of period		323,564
End of period		$ 27,331

Revenue Recognition (Details)

Revenue Recognition (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)contract	Jan. 01, 2018USD ($)	Dec. 31, 2017USD ($)
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total partners’ capital	$ (132,612)		$ (177,179)
ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Number of contracts | contract	4
Effect of Adoption | ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total partners’ capital		$ 10,700

Revenue Recognition - Impact of

Revenue Recognition - Impact of Adopting New Accounting Pronouncement on income Statement (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Commodity sales	$ 158,863	$ 123,521
Services	46,906	40,192
Cost of Sales	150,166	115,468
Direct operating expenses	23,446	17,405
Operating loss	(12,377)	(24,457)
Net loss attributable to the Partnership	(13,883)	(30,184)
General Partner’s interest in net loss	(181)	(420)
Limited Partners’ interest in net loss	(13,702)	$ (29,764)
Adjustments | ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Commodity sales	5,242
Services	(2,681)
Cost of Sales	3,165
Direct operating expenses	(456)
Operating loss	(148)
Net loss attributable to the Partnership	(148)
General Partner’s interest in net loss	(2)
Limited Partners’ interest in net loss	(146)
Amounts without Adoption of Topic 606 | ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Commodity sales	164,105
Services	44,225
Cost of Sales	153,331
Direct operating expenses	22,990
Operating loss	(12,525)
Net loss attributable to the Partnership	(14,031)
General Partner’s interest in net loss	(183)
Limited Partners’ interest in net loss	$ (13,848)

Revenue Recognition - Impact 53

Revenue Recognition - Impact of Adopting New Accounting Pronouncement on Balance Sheet (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable, net	$ 87,418	$ 98,132
Unbilled revenue	67,553
Other current assets	25,265	23,420
Other noncurrent assets	25,249	17,874
Accrued expenses and other current liabilities	88,123	68,854
Liabilities held for sale	3,337	0
Other noncurrent liabilities	15,542	2,080
General Partner interests (960 thousand and 965 thousand units issued and outstanding as of March 31, 2018 and December 31, 2017, respectively)	(88,746)	(96,552)
Limited partner interests	221,346	$ 273,703
Adjustments | ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable, net	(67,553)
Unbilled revenue	67,553
Other current assets	0
Other noncurrent assets	(3,419)
Accrued expenses and other current liabilities	0
Liabilities held for sale	(459)
Other noncurrent liabilities	(13,503)
General Partner interests (960 thousand and 965 thousand units issued and outstanding as of March 31, 2018 and December 31, 2017, respectively)	137
Limited partner interests	10,406
Amounts without Adoption of Topic 606 | ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable, net	19,865
Unbilled revenue	67,553
Other current assets	25,265
Other noncurrent assets	21,830
Accrued expenses and other current liabilities	88,123
Liabilities held for sale	2,878
Other noncurrent liabilities	2,039
General Partner interests (960 thousand and 965 thousand units issued and outstanding as of March 31, 2018 and December 31, 2017, respectively)	(88,609)
Limited partner interests	$ 231,752

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregated Revenues (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 205,769
Gathering and processing
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	7,116
Transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	21,766
Terminalling and storage
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11,833
Other services (2)
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	6,191
Gas Gathering and Processing Services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	35,676
Gas Gathering and Processing Services | Gathering and processing
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	6,250
Gas Gathering and Processing Services | Transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	105
Gas Gathering and Processing Services | Terminalling and storage
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Gas Gathering and Processing Services | Other services (2)
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	434
Liquid Pipelines and Services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	119,773
Liquid Pipelines and Services | Gathering and processing
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Liquid Pipelines and Services | Transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	3,588
Liquid Pipelines and Services | Terminalling and storage
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Liquid Pipelines and Services | Other services (2)
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	403
Natural Gas Transportation Services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	16,063
Natural Gas Transportation Services | Gathering and processing
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Natural Gas Transportation Services | Transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	9,412
Natural Gas Transportation Services | Terminalling and storage
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Natural Gas Transportation Services | Other services (2)
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	10
Offshore Pipelines and Services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	16,859
Offshore Pipelines and Services | Gathering and processing
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	866
Offshore Pipelines and Services | Transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	8,661
Offshore Pipelines and Services | Terminalling and storage
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Offshore Pipelines and Services | Other services (2)
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4,783
Terminalling Services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	17,398
Terminalling Services | Gathering and processing
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Terminalling Services | Transportation
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Terminalling Services | Terminalling and storage
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	11,833
Terminalling Services | Other services (2)
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	561
Natural gas | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	10,980
Natural gas | Gas Gathering and Processing Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,906
Natural gas | Liquid Pipelines and Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Natural gas | Natural Gas Transportation Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	6,637
Natural gas | Offshore Pipelines and Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,437
Natural gas | Terminalling Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
NGLs | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	21,188
NGLs | Gas Gathering and Processing Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	21,150
NGLs | Liquid Pipelines and Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
NGLs | Natural Gas Transportation Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
NGLs | Offshore Pipelines and Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	38
NGLs | Terminalling Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Condensate | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	5,682
Condensate | Gas Gathering and Processing Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	5,648
Condensate | Liquid Pipelines and Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Condensate | Natural Gas Transportation Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Condensate | Offshore Pipelines and Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	34
Condensate | Terminalling Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Crude oil | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	115,782
Crude oil | Gas Gathering and Processing Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Crude oil | Liquid Pipelines and Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	115,782
Crude oil | Natural Gas Transportation Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Crude oil | Offshore Pipelines and Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Crude oil | Terminalling Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Other sales (1) | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	5,231
Other sales (1) | Gas Gathering and Processing Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	183
Other sales (1) | Liquid Pipelines and Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	0
Other sales (1) | Natural Gas Transportation Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	4
Other sales (1) | Offshore Pipelines and Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	40
Other sales (1) | Terminalling Services | Commodity sales:
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 5,004

Revenue Recognition - Reconcili

Revenue Recognition - Reconciliation of Revenues From Contracts With Customers (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	$ 205,769
Gain on commodity derivatives, net	60	$ 365
Total revenue	205,829	164,078
Gas Gathering and Processing Services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	35,676
Gain on commodity derivatives, net	2	(7)
Total revenue	35,678	34,400
Liquid Pipelines and Services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	119,773
Gain on commodity derivatives, net	58	372
Total revenue	119,831	83,783
Natural Gas Transportation Services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	16,063
Gain on commodity derivatives, net	0	0
Total revenue	16,063	12,438
Offshore Pipelines and Services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	16,859
Gain on commodity derivatives, net	0	0
Total revenue	16,859	14,831
Terminalling Services
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	17,398
Gain on commodity derivatives, net	0	0
Total revenue	$ 17,398	$ 18,626

Revenue Recognition - Contract

Revenue Recognition - Contract Balances (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Capitalized Contract Cost [Line Items]
Unbilled revenue	$ 67,553
Billed customer receivables	20,177
Allowance for doubtful accounts	(312)
Accounts receivable, net	87,418	$ 98,132
ASU 2014-09 | Adjustments
Capitalized Contract Cost [Line Items]
Unbilled revenue	67,553
Accounts receivable, net	$ (67,553)

Revenue Recognition - Change in

Revenue Recognition - Change in Contract Balances (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)
Contract with Customer, Asset, Net [Abstract]
Total balance at March 31, 2018	$ 3,419
Noncurrent	3,419
Contract with Customer, Liability [Abstract]
Balance at March 31, 2018	15,377
Current	998
Noncurrent	14,379
Held-for-sale
Contract with Customer, Asset, Net [Abstract]
Total balance at March 31, 2018	0
Contract with Customer, Liability [Abstract]
Balance at March 31, 2018	708
Continuing Operations, Including Assets Held for Sale
Contract with Customer, Asset, Net [Abstract]
Balance at December 31, 2017	0
Topic 606 implementation	2,555
Additions	864
Total balance at March 31, 2018	3,419
Contract with Customer, Liability [Abstract]
Balance at December 31, 2017	2,136
Topic 606 implementation	13,246
Amounts recognized as revenue	(502)
Additions	1,205
Balance at March 31, 2018	$ 16,085

Revenue Recognition - Remaining

Revenue Recognition - Remaining Performance Obligation (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	$ 37,164
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	$ 46,359
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	$ 38,998
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	$ 33,642
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	$ 32,160
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	$ 209,571
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	$ 397,894
Gathering and processing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	9,252
Gathering and processing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	12,743
Gathering and processing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	12,743
Gathering and processing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	12,720
Gathering and processing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	12,467
Gathering and processing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	19,155
Gathering and processing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	79,080
Transportation | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	15,921
Transportation | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	19,233
Transportation | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	18,475
Transportation | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	18,207
Transportation | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	18,100
Transportation | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	190,416
Transportation | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	280,352
Terminalling and storage | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	10,821
Terminalling and storage | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	12,823
Terminalling and storage | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	6,220
Terminalling and storage | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	2,715
Terminalling and storage | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	1,593
Terminalling and storage | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	0
Terminalling and storage | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	34,172
Other services (2) | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	1,170
Other services (2) | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	1,560
Other services (2) | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	1,560
Other services (2) | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	0
Other services (2) | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	0
Other services (2) | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	0
Other services (2) | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation	$ 4,290

Acquisitions and Dispositions59

Acquisitions and Dispositions (Narrative) (Details) $ in Thousands	Nov. 03, 2017USD ($)	Oct. 27, 2017USD ($)	Sep. 29, 2017USD ($)	Sep. 01, 2017USD ($)location	Aug. 08, 2017USD ($)	Jun. 02, 2017USD ($)	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	Feb. 16, 2018USD ($)terminal
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Payments to acquire equity method investments							$ 987	$ 0
Gain on discontinued operations							0	(710)
Refined Products Terminals And Storage Segment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale price per definitive agreement									$ 138,500
Number of terminal facilities | terminal									2
Propane Marketing Services | Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of business and assets, net of cash on hand				$ 170,000
Gain on discontinued operations				47,400
Transaction costs				$ 2,500
Refined Products Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Domestic							$ 2,400	$ 1,800
Propane Business | Propane Marketing Services | Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of service locations divested | location				40
Viosca Knoll
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash payment made to acquire business						$ 32,000
Equity interests acquired (percent)						100.00%
Panther
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total consideration upon acquisition					$ 60,900
Equity interests acquired (percent)					100.00%
Trans-Union Pipeline, L.P. (“Trans-Union”)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total consideration upon acquisition	$ 49,400
Equity interests acquired (percent)	100.00%
Delta House
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Equity interests acquired (percent)			15.50%
Payments to acquire equity method investments			$ 125,400
American Midstream Emerald, LLC | Destin
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total consideration upon acquisition		$ 30,000
Equity interests acquired (percent)		17.00%

Acquisitions and Dispositions60

Acquisitions and Dispositions (Condensed Balance Sheets) (Details) - Refined Products Terminals And Storage Segment - Held-for-sale $ in Thousands	Mar. 31, 2018USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accounts receivable, net	$ 3,376
Inventory	1,571
Other current assets	893
Property, plant and equipment, net	32,129
Goodwill	61,163
Intangible assets	29,403
Other non-current assets	712
Total assets held for sale	129,247
Accounts payable	1,219
Accrued gas purchases	630
Accrued expenses and other current liabilities	881
Contract liabilities, long-term	607
Total liabilities of discontinued operations	$ 3,337

Acquisitions and Dispositions61

Acquisitions and Dispositions (Condensed Statements of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss from discontinued operations before taxes	$ 0	$ (710)
Propane Business | Propane Marketing Services | Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenue		35,554
Total operating expenses		36,305
Operating loss		(751)
Other income		41
Income tax expense		0
Loss from discontinued operations before taxes		(710)
Partnership’s loss from discontinued operations, net of tax		(710)
Depreciation and amortization		3,781
Capital expenditures		1,119
Unrealized gain loss on derivative contracts, net		$ 901

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Crude oil	$ 4,378	$ 1,553
NGLs	282	347
Refined products	0	934
Materials, supplies and equipment	135	132
Total inventory	$ 4,795	$ 2,966

Other Current Assets (Details)

Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid insurance	$ 6,341	$ 8,944
Insurance receivables	1,741	1,741
Due from related parties	5,427	4,362
Other receivables	6,393	5,187
Risk management assets	5,363	3,186
Total other current assets	$ 25,265	$ 23,420

Risk Management Activities (Com

Risk Management Activities (Commodity-related Derivatives) (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2018bblgal	Dec. 31, 2017bblgal
Propane [Member] | Propane, Fixed Price Commodity Swap Contract [Member]
Derivative [Line Items]
Derivative, volume | gal	1,407,000,000	0
Crude oil | Crude Oil, Fixed Price Commodity Swap Contract [Member]
Derivative [Line Items]
Derivative, volume | bbl	17,000,000	0

Risk Management Activities (Int

Risk Management Activities (Interest Rate Swaps) (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Interest Rate Swap
Derivative [Line Items]
Notional Amount	$ 550,000,000	$ 550,000,000

Risk Management Activities (Nar

Risk Management Activities (Narrative) (Details) - Weather Derivative - USD ($)	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Potential proceeds from derivative contract	$ 30,000,000
Term of contract	1 year
Debt instrument, unamortized premium	$ 200,000	$ 500,000

Risk Management Activities (Fai

Risk Management Activities (Fair Value of Commodity Derivatives) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Derivative Asset [Abstract]
Gross Risk Management Position	$ 16,892	$ 11,994
Netting Adjustments	(5)	0
Net Risk Management Position	16,887	11,994
Derivative Liability [Abstract]
Gross Risk Management Position	(64)	0
Netting Adjustments	5	0
Net Risk Management Position	(59)	0
Other Current Assets | Commodity Contract
Derivative Asset [Abstract]
Gross Risk Management Position	5	0
Derivative Liability [Abstract]
Gross Risk Management Position	0	0
Other Current Assets | Interest Rate Swap
Derivative Asset [Abstract]
Gross Risk Management Position	5,132	2,678
Derivative Liability [Abstract]
Gross Risk Management Position	0	0
Other Current Assets | Weather Derivative
Derivative Asset [Abstract]
Gross Risk Management Position	231	509
Derivative Liability [Abstract]
Gross Risk Management Position	0	0
Other Assets, Net | Interest Rate Swap
Derivative Asset [Abstract]
Gross Risk Management Position	11,524	8,807
Derivative Liability [Abstract]
Gross Risk Management Position	0	0
Accrued Expenses and Other Liabilities | Commodity Contract
Derivative Asset [Abstract]
Gross Risk Management Position	0	0
Derivative Liability [Abstract]
Gross Risk Management Position	(64)	0
Risk Management Assets
Derivative Asset [Abstract]
Gross Risk Management Position	5,368	3,187
Netting Adjustments	(5)	0
Net Risk Management Position	5,363	3,187
Risk Management Assets - Long Term
Derivative Asset [Abstract]
Gross Risk Management Position	11,524	8,807
Netting Adjustments	0	0
Net Risk Management Position	11,524	8,807
Risk Management Liabilities
Derivative Liability [Abstract]
Gross Risk Management Position	(64)	0
Netting Adjustments	5	0
Net Risk Management Position	$ (59)	$ 0

Risk Management Activities (Rea

Risk Management Activities (Realized and Unrealized Gains (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Derivatives, Fair Value [Line Items]
Gain on commodity derivatives, net	$ 60	$ 365
Commodity Contract
Derivatives, Fair Value [Line Items]
Gain on commodity derivatives, net	1,191	98
Unrealized gain (loss) on derivatives	5,112	(372)
Commodity Contract | Gain (Loss) on Derivative Instruments
Derivatives, Fair Value [Line Items]
Gain on commodity derivatives, net	119	420
Unrealized gain (loss) on derivatives	(59)	(55)
Commodity Contract | Interest Expense
Derivatives, Fair Value [Line Items]
Gain on commodity derivatives, net	1,350	(65)
Unrealized gain (loss) on derivatives	5,171	(317)
Commodity Contract | Direct operating expenses [Member]
Derivatives, Fair Value [Line Items]
Gain on commodity derivatives, net	(278)	(257)
Unrealized gain (loss) on derivatives	$ 0	$ 0

Property, Plant and Equipment69

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	$ 1,422,217	$ 1,436,463
Accumulated depreciation	(341,320)	(340,878)
Property, plant and equipment, net	1,080,897	1,095,585
Land [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	16,366	18,145
Construction in progress [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	83,013	55,622
Buildings and improvements [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	15,476	16,235
Transportation equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	22,597	22,697
Processing and treating plants [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	123,580	123,138
Pipelines, compressors and right-of-way [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	975,213	974,301
Storage [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	124,037	146,105
Equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment gross	$ 61,935	$ 80,220
Minimum | Buildings and improvements [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	4 years
Minimum | Transportation equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	5 years
Minimum | Processing and treating plants [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	8 years
Minimum | Pipelines, compressors and right-of-way [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	3 years
Minimum | Storage [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	3 years
Minimum | Equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	3 years
Maximum | Buildings and improvements [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	40 years
Maximum | Transportation equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	15 years
Maximum | Processing and treating plants [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	40 years
Maximum | Pipelines, compressors and right-of-way [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	40 years
Maximum | Storage [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	40 years
Maximum | Equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property plant and equipment in useful life	31 years

Property, Plant and Equipment70

Property, Plant and Equipment (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$ 1,422,217		$ 1,436,463
Depreciation	18,600	$ 18,500
Interest costs capitalized	600	$ 1,000
FERC Regulated Assets [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	369,500		367,600
Processing And Treating Plants [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	123,580		123,138
Pipelines [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$ 975,213		$ 974,301

Goodwill and Intangible Asset71

Goodwill and Intangible Assets (Schedule of Goodwill) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill	$ 67,985	$ 128,866
Liquid Pipelines and Services
Goodwill [Line Items]
Goodwill	35,710	35,708
Terminalling Services
Goodwill [Line Items]
Goodwill	27,303	88,466
Offshore Pipelines and Services
Goodwill [Line Items]
Goodwill	$ 4,972	$ 4,692

Goodwill and Intangible Asset72

Goodwill and Intangible Assets Goodwill and Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 2.7	$ 6.6
Remainder of 2018	7.6
2,019	10.2
2,020	10.2
2,021	10.2
2,022	$ 9.3
Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived intangible asset, useful life	5 years
Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived intangible asset, useful life	30 years

Goodwill and Intangible Asset73

Goodwill and Intangible Assets Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Customer relationships	$ 215,129	$ 260,868
Finite-Lived Intangible Assets, Accumulated Amortization	(73,502)	(86,858)
Finite-Lived Intangible Assets, Net	141,627	174,010
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Customer relationships	64,744	110,483
Finite-Lived Intangible Assets, Accumulated Amortization	(14,806)	(29,965)
Finite-Lived Intangible Assets, Net	49,938	80,518
Customer Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Customer relationships	94,692	94,692
Finite-Lived Intangible Assets, Accumulated Amortization	(49,420)	(48,173)
Finite-Lived Intangible Assets, Net	45,272	46,519
Dedicated Acreage [Member]
Finite-Lived Intangible Assets [Line Items]
Customer relationships	42,547	42,547
Finite-Lived Intangible Assets, Accumulated Amortization	(6,560)	(6,216)
Finite-Lived Intangible Assets, Net	35,987	36,331
Collaborative Arrangement [Member]
Finite-Lived Intangible Assets [Line Items]
Customer relationships	11,884	11,884
Finite-Lived Intangible Assets, Accumulated Amortization	(1,627)	(1,415)
Finite-Lived Intangible Assets, Net	10,257	10,469
Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Customer relationships	1,064	1,064
Finite-Lived Intangible Assets, Accumulated Amortization	(1,064)	(1,064)
Finite-Lived Intangible Assets, Net	0	0
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Customer relationships	198	198
Finite-Lived Intangible Assets, Accumulated Amortization	(25)	(25)
Finite-Lived Intangible Assets, Net	$ 173	$ 173

Investment in Unconsolidated 74

Investment in Unconsolidated Affiliates Partnership's Equity Investments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Balances	$ 348,434
Earnings in unconsolidated affiliates	12,673	$ 15,402
Cash Call For Expansion Projects	2,018
Distributions	(23,854)
Balances	$ 339,271
FPS [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	35.70%		35.70%
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Balances	$ 90,412
Earnings in unconsolidated affiliates	3,227
Cash Call For Expansion Projects	0
Distributions	(2,247)
Balances	$ 91,392
OGL [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	35.70%		35.70%
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Balances	$ 46,932
Earnings in unconsolidated affiliates	2,715
Cash Call For Expansion Projects	0
Distributions	(4,278)
Balances	$ 45,369
Destin
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	66.70%		66.70%
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Balances	$ 124,245
Earnings in unconsolidated affiliates	2,377
Cash Call For Expansion Projects	0
Distributions	(10,734)
Balances	$ 115,888
Tri-State [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	16.70%		16.70%
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Balances	$ 53,057
Earnings in unconsolidated affiliates	854
Cash Call For Expansion Projects	0
Distributions	(2,034)
Balances	$ 51,877
Okeanos [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	66.70%		66.70%
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Balances	$ 22,445
Earnings in unconsolidated affiliates	2,132
Cash Call For Expansion Projects	0
Distributions	(4,378)
Balances	$ 20,199
Wilprise [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	25.30%		25.30%
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Balances	$ 4,689
Earnings in unconsolidated affiliates	258
Cash Call For Expansion Projects	0
Distributions	(183)
Balances	$ 4,764
Cayenne JV [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	50.00%		50.00%
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Balances	$ 6,654
Earnings in unconsolidated affiliates	1,110
Cash Call For Expansion Projects	2,018
Distributions	0
Balances	$ 9,782

Investment in Unconsolidated 75

Investment in Unconsolidated Affiliates Financial Information for the Partnership's Equity Investments - Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Equity Method Investments and Joint Ventures [Abstract]
Current assets	$ 64,381	$ 80,405
Non-current assets	1,279,417	1,288,862
Current liabilities	114,724	130,904
Non-current liabilities	$ 438,496	$ 436,584

Investment in Unconsolidated 76

Investment in Unconsolidated Affiliates Financial Information for the Partnership's Equity Investments - Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Equity Method Investments and Joint Ventures [Abstract]
Revenue	$ 56,898	$ 93,870
Operating expenses	6,292	8,436
Net income	$ 32,845	$ 69,285

Accrued Expenses and Other Cu77

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Other Liabilities Disclosure [Abstract]
Capital expenditures	$ 20,880	$ 10,721
Accrued interest	15,590	3,190
Convertible preferred unit distributions	8,354	0
Employee compensation	149	90
Current portion of asset retirement obligation	6,416	6,416
Additional Blackwater acquisition consideration	5,000	5,000
Transaction costs	3,732	3,408
Customer deposits	1,136	1,109
Taxes payable	4,018	5,263
Due to related parties	3,212	6,609
Deferred financing costs	0	266
Contingent liabilities associated with VKGS and Panther	2,098	2,099
Royalties, gas imbalance and leases payables	7,119	7,905
Professional fees	2,024	1,848
Accrued corporate expenses	1,697	2,487
Accrued operating expenses	4,881	6,609
Other	1,817	5,834
Total accrued expenses and other current liabilities	$ 88,123	$ 68,854

Asset Retirement Obligations (D

Asset Retirement Obligations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Non-current balance	$ 66,194
Current portion of asset retirement obligation	6,416
Balances at December 31, 2017	72,610
Additions	260
Expenditures	0
Accretion expense	440
Balances at March 31, 2018	72,610	$ 73,310	$ 72,610
Less: current portion	6,416
Noncurrent asset retirement obligation	$ 66,894
Restricted cash and cash equivalents		$ 5,000	$ 5,000

Debt Obligations (Details)

Debt Obligations (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	May 10, 2016
Debt Instrument [Line Items]
Long-term	$ 1,229,434	$ 1,218,238
Unamortized debt issuance costs	(9,530)	(9,231)
Total debt obligations	1,219,904	1,209,007
Less: current portion	(5,058)	(7,551)
Long-term debt	1,214,846	1,201,456
Senior Notes | 8.50% Senior Notes
Debt Instrument [Line Items]
Long-term	$ 425,000	425,000
Debt instrument, stated interest rate (percent)	8.50%
Senior Notes | 3.77% Senior Notes
Debt Instrument [Line Items]
Long-term	$ 57,817	58,324
Debt instrument, stated interest rate (percent)	3.77%
Senior Notes | 3.97% Trans-Union Secured Senior notes
Debt Instrument [Line Items]
Long-term	$ 31,586	$ 32,025
Debt instrument, stated interest rate (percent)	3.97%	3.97%	3.97%
Other Debt Obligations [Member]
Debt Instrument [Line Items]
Long-term	$ 2,431	$ 4,989
Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit facility	$ 712,600	$ 697,900

Debt Obligations (Narrative) (D

Debt Obligations (Narrative) (Details)

Dec. 28, 2016USD ($)

Sep. 30, 2016USD ($)

May 10, 2016USD ($)

Mar. 31, 2018USD ($)

Dec. 31, 2017USD ($)

Sep. 30, 2017

Jun. 30, 2017

Mar. 31, 2017USD ($)

Dec. 14, 2018

Dec. 19, 2017USD ($)

Mar. 08, 2017USD ($)

Dec. 31, 2016USD ($)

Apr. 25, 2016USD ($)

Debt Instrument [Line Items]

Proceeds from debt issuance

$ 294,000,000

Debt issuance costs

6,000,000

Additional debt issuance costs

2,700,000

Restricted Cash

$ 23,317,000

$ 25,397,000

$ 27,331,000

$ 323,564,000

Fourth Amendment

Debt Instrument [Line Items]

Line of credit facility, current borrowing capacity

$ 900,000,000

$ 750,000,000

Maximum borrowing limit

1,100,000,000

Sublimit for borrowings

$ 30,000,000

Letters of credit outstanding, amount

31,000,000

Borrowings outstanding

$ 712,600,000

Fourth Amendment | Maximum

Debt Instrument [Line Items]

Ratio of Indebtedness to Net Capital

5

Ratio of indebtedness to net capital, after allowed acquisition

5.50

5.50

5

5.50

5.50

Debt instrument, interest coverage ratio

3.50

Fourth Amendment | Minimum

Debt Instrument [Line Items]

Debt instrument, interest coverage ratio

2.50

8.50% Senior Notes | Senior Notes

Debt Instrument [Line Items]

Debt instrument, stated interest rate (percent)

8.50%

8.50% Senior unsecured notes

Debt Instrument [Line Items]

Senior notes

$ 418,421,000

8.50% Senior unsecured notes | Senior Notes

Debt Instrument [Line Items]

Debt instrument, face amount

$ 300,000,000

Debt instrument, stated interest rate (percent)

8.50%

8.50%

8.50%

Proceeds from debt issuance

$ 291,300,000

Accrual rate (percent)

0.25%

Senior notes

$ 418,078,000

Fair value, debt

$ 430,400,000

8.50% Senior unsecured notes | Senior Notes | Maximum

Debt Instrument [Line Items]

Accrual rate (percent)

1.00%

$125 Million 8.5% New Issuance ('Tag on') | Senior Notes

Debt Instrument [Line Items]

Debt instrument, face amount

$ 125,000,000

Debt instrument, stated interest rate (percent)

8.50%

Debt issuance costs

$ 3,000,000

3.77% Senior Notes | Senior Notes

Debt Instrument [Line Items]

Debt instrument, stated interest rate (percent)

3.77%

3.77% Senior secured notes (Non-recourse)

Debt Instrument [Line Items]

Senior notes

$ 54,682,000

$ 55,198,000

3.77% Senior secured notes (Non-recourse) | Senior Notes

Debt Instrument [Line Items]

Debt instrument, face amount

$ 60,000,000

Debt instrument, stated interest rate (percent)

3.77%

3.77%

3.77%

Debt issuance costs

$ 2,300,000

Fair value, debt

$ 51,800,000

Restricted Cash

15,200,000

Net proceeds from debt issuance

57,700,000

Average quarterly principal payment

$ 1,100,000

3.97% Trans-Union Secured Senior notes

Debt Instrument [Line Items]

Senior notes

$ 29,486,000

$ 29,937,000

3.97% Trans-Union Secured Senior notes | Senior Notes

Debt Instrument [Line Items]

Debt instrument, face amount

$ 35,000,000

Debt instrument, stated interest rate (percent)

3.97%

3.97%

3.97%

Debt issuance costs

$ 400,000

Fair value, debt

$ 28,700,000

Average quarterly principal payment

500,000

Proceeds from debt issuance

$ 34,600,000

Revolving Credit Facility

Debt Instrument [Line Items]

Consolidated total leverage ratio

5.19

Debt instrument, interest coverage ratio

3.43

Borrowings outstanding

$ 712,600,000

$ 697,900,000

Revolving Credit Facility | Fourth Amendment | Eurodollar

Debt Instrument [Line Items]

Debt instrument, basis spread on variable rate

1.00%

Revolving Credit Facility | Fourth Amendment | Eurodollar | Maximum

Debt Instrument [Line Items]

Line of credit facility, unused capacity, commitment fee percentage

0.50%

Revolving Credit Facility | Fourth Amendment | Eurodollar | Minimum

Debt Instrument [Line Items]

Line of credit facility, unused capacity, commitment fee percentage

0.375%

Revolving Credit Facility | Fourth Amendment | Federal Funds Rate

Debt Instrument [Line Items]

Debt instrument, basis spread on variable rate

0.50%

Letter of Credit | Fourth Amendment

Debt Instrument [Line Items]

Line of credit facility, current borrowing capacity

$ 100,000,000

Variable Rate Component, Component One | Revolving Credit Facility | Fourth Amendment | Eurodollar | Maximum

Debt Instrument [Line Items]

Debt instrument, basis spread on variable rate

3.25%

Variable Rate Component, Component One | Revolving Credit Facility | Fourth Amendment | Eurodollar | Minimum

Debt Instrument [Line Items]

Debt instrument, basis spread on variable rate

2.00%

Variable Rate Component, Component Two | Revolving Credit Facility | Fourth Amendment | Eurodollar | Maximum

Debt Instrument [Line Items]

Debt instrument, basis spread on variable rate

2.25%

Variable Rate Component, Component Two | Revolving Credit Facility | Fourth Amendment | Eurodollar | Minimum

Debt Instrument [Line Items]

Debt instrument, basis spread on variable rate

1.00%

Forecast | 8.50% Senior unsecured notes | Senior Notes

Debt Instrument [Line Items]

Number of days within closing of equity offering

180 days

Redemption price (percent)

108.50%

Forecast | 8.50% Senior unsecured notes | Senior Notes | Maximum

Debt Instrument [Line Items]

Percentage of principal that can be redeemed (percent)

35.00%

Forecast | 8.50% Senior unsecured notes | Senior Notes | Minimum

Debt Instrument [Line Items]

Percentage of outstanding debt principal that can be redeemed (percent)

65.00%

Debt Obligation, Redemption Pri

Debt Obligation, Redemption Prices (Details) - Senior Notes - 8.50% Senior unsecured notes	3 Months Ended
	Mar. 31, 2018
2,018
Debt Instrument [Line Items]
Redemption price (percent)	104.25%
2,019
Debt Instrument [Line Items]
Redemption price (percent)	102.125%
2020 and thereafter
Debt Instrument [Line Items]
Redemption price (percent)	100.00%

Convertible Preferred Units (Sc

Convertible Preferred Units (Schedule of Convertible Preferred Units) (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Increase (Decrease) in Partners' Capital [Roll Forward]
Convertible preferred units, Beginning Balance, Amount,	$ 317,180
Paid in kind unit distributions, Amount	30,120	$ 33,967
Convertible preferred units, Ending Balance, Amount,	317,180
Unit Distribution [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Paid in kind unit distributions, Amount	$ 0	$ 2,733
Series A [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Convertible preferred units, Beginning Balance, Units	10,719
Convertible preferred units, Ending Balance, Units	11,010
Convertible preferred units, Beginning Balance, Amount,	$ 191,798
Convertible preferred units, Ending Balance, Amount,	$ 191,798
Series A [Member] | Unit Distribution [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Paid in kind unit distributions, Units	291
Paid in kind unit distributions, Amount	$ 0
Series C [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Convertible preferred units, Beginning Balance, Units	8,965
Convertible preferred units, Ending Balance, Units	9,242
Convertible preferred units, Beginning Balance, Amount,	$ 125,382
Convertible preferred units, Ending Balance, Amount,	$ 125,382
Series C [Member] | Unit Distribution [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Paid in kind unit distributions, Units	277
Paid in kind unit distributions, Amount	$ 0

Convertible Preferred Units (De

Convertible Preferred Units (Details)	Apr. 26, 2018$ / shares	Apr. 25, 2016$ / sharesshares	Jul. 27, 2015USD ($)$ / shares	Apr. 15, 2013USD ($)$ / sharesshares	Mar. 31, 2018USD ($)$ / sharesshares	Mar. 31, 2017$ / shares	Dec. 31, 2015USD ($)shares	Dec. 31, 2017shares
Preferred Units [Line Items]
Distribution declared per common unit (in usd per share)					$ 0.4125	$ 0.4125
Preferred, units, outstanding (in shares) | shares					52,853,000			52,711,000
Series A [Member]
Preferred Units [Line Items]
Sale of units percentage				90.00%
Partners' Capital Account, Units | shares				5,142,857	11,010,000			10,719,000
Conversion price (usd per share)					$ 15.16
Convertible Stock, Conversion Ratio					1.1483
Distribution per unit				$ 0.4125
Series A-2 [Member]
Preferred Units [Line Items]
Conversion price (usd per share)					$ 15.16
Convertible Stock, Conversion Ratio					1.1483
Proceeds from Issuance of Convertible Preferred Units | $							$ 45,000,000
Investment options, exercise price (in usd per share)			$ 17.50
Call right defined acquisition value | $			$ 100,000,000
Series C [Member]
Preferred Units [Line Items]
Partners' Capital Account, Units | shares					9,242,000			8,965,000
Conversion price (usd per share)					$ 13.33
Convertible Stock, Conversion Ratio					1.0448
Investment options, exercise price (in usd per share)		$ 14
Shares issued upon conversion (in shares) | shares		1
Class of warrant, number of securities called by warrants (in shares) | shares		800,000
Class of warrant, exercise price of warrants (in usd per share)		$ 7.25
Warrant, exercisable period		7 years			7 years
Fair value of warrant unit (in usd per share)					$ 4.41
Expected dividend rate					18.00%
Fair value assumptions, expected volatility rate					42.00%
Issuance of warrant | $					$ 4,500,000
High Point Infrastructure Partners, LLC [Member] | Series A [Member]
Preferred Units [Line Items]
Issuance of units | $				$ 15,000,000
Magnolia Infrastructure Partners, LLC | Issuance of Preferred Units [Member] | Series A-2 [Member]
Preferred Units [Line Items]
Partners' Capital Account, Units, Sold in Private Placement | shares							2,571,430
ArcLight [Member] | Issuance of Preferred Units [Member] | Series C [Member]
Preferred Units [Line Items]
Partners' Capital Account, Units, Sold in Private Placement | shares		8,571,429
Subsequent Event
Preferred Units [Line Items]
Distribution declared per common unit (in usd per share)	$ 0.4125

Partners Capital (Narrative) (D

Partners Capital (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Class of Stock [Line Items]
General Partners' Capital Account, Period Distribution Amount	$ 0	$ 100,000
General partner interest	1.30%
Limited partner interests	98.70%
Proceeds from General Partner	$ 9,870,000	$ 4,123,000
Fair Value input, distribution growth rate	1.00%
General Partner
Class of Stock [Line Items]
General Partners' Capital Account, Units Issued	0	8,665
Proceeds from General Partner	$ 9,870,000	$ 123,000
Minimum
Class of Stock [Line Items]
Fair value input, option value (dollars per unit)	$ 0.31
Fair value inputs, discount rate (percent)	5.57%
Maximum
Class of Stock [Line Items]
Fair value input, option value (dollars per unit)	$ 2.83
Fair value inputs, discount rate (percent)	6.23%

Partners_ Capital Outstanding U

Partners’ Capital Outstanding Units (Details) shares in Thousands	3 Months Ended
	Mar. 31, 2018shares
Increase (Decrease) in Partners' Capital [Roll Forward]
Balances at December 31, 2017	965
Balances at December 31, 2017	52,711
Balances at March 31, 2018	965
Balances at March 31, 2018	52,853
General Partner | Long Term Incentive Plan [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' Capital Account Increase	0
Limited Partner [Member] | Long Term Incentive Plan [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' Capital Account Increase	142

Partners_ Capital Distributions

Partners’ Capital Distributions (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Class of Stock [Line Items]
General Partner's distribution	$ 30,120	$ 33,967
Limited Partner [Member]
Class of Stock [Line Items]
General Partner's distribution	29,728	33,685
General Partner
Class of Stock [Line Items]
General Partner's distribution	392	282
Paid / Accrued [Member]
Class of Stock [Line Items]
General Partner's distribution	22,035	32,198
Paid / Accrued [Member] | Limited Partner [Member]
Class of Stock [Line Items]
General Partner's distribution	21,745	24,915
Paid / Accrued [Member] | General Partner
Class of Stock [Line Items]
General Partner's distribution	290	167
Accrued Cash [Member]
Class of Stock [Line Items]
General Partner's distribution	8,354	8,885
Unit Distribution [Member]
Class of Stock [Line Items]
General Partner's distribution	0	2,733
Series A [Member] | Paid / Accrued [Member]
Class of Stock [Line Items]
General Partner's distribution	0	2,527
Series A [Member] | Accrued Cash [Member]
Class of Stock [Line Items]
General Partner's distribution	4,542	4,296
Series A [Member] | Unit Distribution [Member]
Class of Stock [Line Items]
General Partner's distribution	0	2,733
Series C [Member] | Paid / Accrued [Member]
Class of Stock [Line Items]
General Partner's distribution	0	3,627
Series C [Member] | Accrued Cash [Member]
Class of Stock [Line Items]
General Partner's distribution	3,812	3,627
Series C [Member] | Unit Distribution [Member]
Class of Stock [Line Items]
General Partner's distribution	0	0
Series D [Member] | Paid / Accrued [Member]
Class of Stock [Line Items]
General Partner's distribution	0	962
American Midstream Partners L. P. [Member] | Series D [Member] | Accrued Cash [Member]
Class of Stock [Line Items]
General Partner's distribution	$ 0	$ 962

Net Loss per Limited Partner 87

Net Loss per Limited Partner Unit Net Loss per Limited Partner Unit (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Net loss	$ (13,838)	$ (28,171)
Less: Net income attributable to noncontrolling interests	45	1,303
Net income (loss) from continuing operations attributable to the Partnership	(13,883)	(29,474)
General Partner's distribution	30,120	33,967
General partner’s share in undistributed loss	(583)	(560)
Net loss from continuing operations available to Limited Partners	(21,944)	(37,999)
Net loss from discontinued operations available to Limited Partners	0	(710)
Net loss available to Limited Partners	$ (21,944)	$ (38,709)
Weighted average number of common units outstanding: basic and diluted (shares)	52,769	51,451
Limited Partners' net income (loss) from continuing operations per unit (in usd per unit)	$ (0.42)	$ (0.74)
Limited Partners' net income (loss) from discontinued operations per unit (in usd per unit)	0	(0.01)
Limited Partners' net loss per common unit (in usd per share)	$ (0.42)	$ (0.75)
Series A [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Distributions	$ 4,542	$ 4,296
Series C [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Distributions	3,812	3,627
Series D [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Distributions	0	962
General Partner
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
General Partner's distribution	392	282
General Partner | Accrued [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
General Partner's distribution	$ 290	$ 200

Incentive Compensation(Narrativ

Incentive Compensation(Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting increments			25.00%
Equity compensation expense	$ 1,014,000	$ 4,037,000
Unvested options (shares)	245,000
Unrecognized compensation expense			$ 100,000
Employer matching	$ 800,000	500,000
Parent [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity compensation expense	$ 1,014,000	4,037,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Restricted Stock Units (RSUs) [Member] | Parent [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity compensation expense	$ 700,000	4,000,000
Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common units available for future grants (shares)	4,308,985
Long Term Incentive Plan [Member] | Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	38,000
Forfeited (in shares)	154,693
Vested (in shares)	193,698
Granted (in usd per share)	$ 11.88
Forfeited (in usd per share)	7.12
Vested (in usd per share)	$ 4.49
JPE 2014 Long-Term Incentive Plan (“JPE LTIP”) [Member] | Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	0
Equity compensation expense	$ 300,000	$ 0
Unrecognized compensation expense	$ 5,900,000
Unvested PSUs (in shares)	524,000

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Expenses associated with operating leases and service contracts	$ 2.6	$ 1.9

Related Party Transactions (Na

Related Party Transactions (Narrative) (Details) - USD ($)	3 Months Ended			12 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2013
Related Party Transaction [Line Items]
Contributions		$ 9,870,000	$ 123,000
Revenue from related parties		600,000	600,000
Due from related parties		5,427,000		$ 4,362,000
Direct operating expenses		23,446,000	17,405,000
Direct operating expenses		22,692,000	30,113,000
Blackwater
Related Party Transaction [Line Items]
Additional consideration						$ 5,000,000
Additional Blackwater acquisition consideration					$ 5,000,000
Republic Midstream, LLC (“Republic”)
Related Party Transaction [Line Items]
Monthly fee				100,000
Receivable balance from affiliate		100,000		800,000
Capstone Ventures, LLC
Related Party Transaction [Line Items]
Revenue from related parties			200,000
AMID Merger GP II, LLC
Related Party Transaction [Line Items]
Receivable balance from affiliate		2,500,000		$ 2,500,000
Director | Consolidated Asset Management Services, LLC (CAMS)
Related Party Transaction [Line Items]
Ownership interest (percent)				22.00%
Other Current Liabilities | General Partner
Related Party Transaction [Line Items]
Due to Related Parties		3,700,000		$ 6,500,000
Other Current Assets
Related Party Transaction [Line Items]
Due from related parties		2,500,000		900,000
Consolidated Asset Management Services, LLC (CAMS) | Affiliated Entity
Related Party Transaction [Line Items]
Receivable balance from affiliate		0		0
Purchases from related party		100,000	100,000
CIMA Energy Ltd | Affiliated Entity
Related Party Transaction [Line Items]
Due to Related Parties		0		0
Revenue from related parties		2,100,000	1,400,000
Receivable balance from affiliate		0		$ 0
Purchases from related party		$ 700,000	$ 700,000
Subsequent Event | Magnolia Infrastructure Partners, LLC
Related Party Transaction [Line Items]
Proceeds from additional capital contribution	$ 9,400,000

Supplemental Cash Flow Inform91

Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Limited Partners' Capital Account [Line Items]
Interest payments, net of capitalized interest	$ 6,927	$ 12,610
Increase in accrued property, plant and equipment purchases	10,159	2,233
Contributions	9,870	4,123
Accrued distributions on convertible preferred units	8,354	8,885
Paid-in-kind distributions on convertible preferred units	0	2,733
Limited Partner [Member]
Limited Partners' Capital Account [Line Items]
Contributions	$ 0	$ 4,000

Reportable Segments - Reconcili

Reportable Segments - Reconciliation of Gross Profit (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Direct operating expenses	$ 23,446	$ 17,405
Operating Income (Loss)	(12,377)	(24,457)
Derivative, Gain (Loss) on Derivative, Net	60	365
Corporate expenses	22,692	30,113
Depreciation, amortization and accretion	21,997	25,570
Gain on sale of assets, net	(95)	(21)
Interest expense	13,876	17,956
Other income	(22)	37
Other, net	27	392
Income tax expense	280	1,123
Loss from discontinued operations, net of tax	0	710
Less: Net income attributable to noncontrolling interests	45	1,303
Net loss attributable to the Partnership	(13,883)	(30,184)
Liquid Pipelines and Services
Segment Reporting Information [Line Items]
Segment gross margin	7,271	6,634
Direct operating expenses	2,976	2,453
Derivative, Gain (Loss) on Derivative, Net	58	372
Natural Gas Transportation Services
Segment Reporting Information [Line Items]
Segment gross margin	10,688	6,119
Direct operating expenses	1,673	1,235
Derivative, Gain (Loss) on Derivative, Net	0	0
Offshore Pipelines and Services
Segment Reporting Information [Line Items]
Segment gross margin	25,316	25,802
Direct operating expenses	7,795	2,579
Derivative, Gain (Loss) on Derivative, Net	0	0
Terminalling Services
Segment Reporting Information [Line Items]
Segment gross margin	8,053	11,160
Direct operating expenses	4,322	3,073
Derivative, Gain (Loss) on Derivative, Net	0	0
All Operating Segments, Excluding Terminalling Segment [Member]
Segment Reporting Information [Line Items]
Direct operating expenses	$ 19,124	$ 14,332

Reportable Segments (Narrative)

Reportable Segments (Narrative) (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018USD ($)segments	Mar. 31, 2017USD ($)	Dec. 31, 2017segment
Segment Reporting Information [Line Items]
Number of reportable segments	5		5
Direct operating expenses	$ 23,446	$ 17,405
Propane business expenses excluded from capital expenditure	25,946	19,101
Liquid Pipelines and Services
Segment Reporting Information [Line Items]
Direct operating expenses	2,976	2,453
Propane business expenses excluded from capital expenditure	6,414	370
Natural Gas Transportation Services
Segment Reporting Information [Line Items]
Direct operating expenses	1,673	1,235
Propane business expenses excluded from capital expenditure	1,338	10,228
Offshore Pipelines and Services
Segment Reporting Information [Line Items]
Direct operating expenses	7,795	2,579
Propane business expenses excluded from capital expenditure	6,350	220
Terminalling Services
Segment Reporting Information [Line Items]
Direct operating expenses	4,322	3,073
Propane business expenses excluded from capital expenditure	$ 3,705	1,811
Propane Business
Segment Reporting Information [Line Items]
Propane business expenses excluded from capital expenditure		$ 1,100

Reportable Segments (Details)

Reportable Segments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment information
Revenue	$ 205,769	$ 163,713
Gain on commodity derivatives, net	60	365
Total revenue	205,829	164,078
Earnings in unconsolidated affiliates	12,673	15,402
Cost of Sales	150,166	115,468
Direct operating expenses	23,446	17,405
Corporate expenses	22,692	30,113
Depreciation, amortization and accretion	21,997	25,570
Gain on sale of assets, net	(95)	(21)
Total operating expenses	218,206	188,535
Interest expense	13,876	17,956
Other income (expense), net	22	(37)
Loss from continuing operations before income taxes	(13,558)	(27,048)
Income tax expense	280	1,123
Loss from continuing operations	(13,838)	(28,171)
Loss from discontinued operations	0	(710)
Loss from discontinued operations, net of tax	0	(710)
Net loss	(13,838)	(28,881)
Less: Net income attributable to noncontrolling interests	45	1,303
Less: Net income attributable to noncontrolling interests	45	1,303
Net loss attributable to the Partnership	(13,883)	(30,184)
Gas Gathering and Processing Services
Segment information
Revenue	35,676	34,407
Gain on commodity derivatives, net	2	(7)
Total revenue	35,678	34,400
Earnings in unconsolidated affiliates	0	0
Cost of Sales	23,056	23,187
Direct operating expenses	6,680	8,065
Segment gross margin	12,653	11,251
Liquid Pipelines and Services
Segment information
Revenue	119,773	83,411
Gain on commodity derivatives, net	58	372
Total revenue	119,831	83,783
Earnings in unconsolidated affiliates	2,222	1,088
Cost of Sales	114,805	78,285
Direct operating expenses	2,976	2,453
Segment gross margin	7,271	6,634
Natural Gas Transportation Services
Segment information
Revenue	16,063	12,438
Gain on commodity derivatives, net	0	0
Total revenue	16,063	12,438
Earnings in unconsolidated affiliates	0	0
Cost of Sales	5,288	6,260
Direct operating expenses	1,673	1,235
Segment gross margin	10,688	6,119
Offshore Pipelines and Services
Segment information
Revenue	16,859	14,831
Gain on commodity derivatives, net	0	0
Total revenue	16,859	14,831
Earnings in unconsolidated affiliates	10,451	14,314
Cost of Sales	1,994	3,343
Direct operating expenses	7,795	2,579
Segment gross margin	25,316	25,802
Terminalling Services
Segment information
Revenue	17,398	18,626
Gain on commodity derivatives, net	0	0
Total revenue	17,398	18,626
Earnings in unconsolidated affiliates	0	0
Cost of Sales	5,023	4,393
Direct operating expenses	4,322	3,073
Segment gross margin	$ 8,053	$ 11,160

Reportable Segments - Assets (D

Reportable Segments - Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Assets	$ 1,933,262		$ 1,923,466
Investments in unconsolidated affiliates	339,271		348,434
Total Capital expenditures	25,946	$ 19,101
Gas Gathering and Processing Services
Segment Reporting Information [Line Items]
Assets	400,757		404,872
Total Capital expenditures	6,654	4,383
Liquid Pipelines and Services
Segment Reporting Information [Line Items]
Assets	379,592		359,646
Investments in unconsolidated affiliates	66,421		64,399
Total Capital expenditures	6,414	370
Offshore Pipelines and Services
Segment Reporting Information [Line Items]
Assets	537,548		553,213
Investments in unconsolidated affiliates	272,850		284,035
Total Capital expenditures	6,350	220
Natural Gas Transportation Services
Segment Reporting Information [Line Items]
Assets	267,782		268,991
Total Capital expenditures	1,338	10,228
Terminalling Services
Segment Reporting Information [Line Items]
Assets	291,662		293,085
Total Capital expenditures	3,705	1,811
Other Segments
Segment Reporting Information [Line Items]
Assets	55,921		$ 43,659
Total Capital expenditures	$ 1,485	$ 2,089

Subsequent Events (Details)

Subsequent Events (Details) - $ / shares shares in Thousands	Apr. 26, 2018	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Subsequent Event [Line Items]
Preferred, units, outstanding (in shares)		52,853		52,711
Distribution declared per common unit (in usd per share)		$ 0.4125	$ 0.4125
Subsequent Event
Subsequent Event [Line Items]
Distribution declared per common unit (in usd per share)	$ 0.4125
Distribution made to limited partner, distributions declared, per unit, annualized basis (in usd per share)	$ 1.65

Uncategorized Items - amid-2018

Label	Element	Value
Contract with Customer, Asset, Net, Current	us-gaap_ContractWithCustomerAssetNetCurrent	$ 0