Southcross Energy Partners 10-Q 10 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information	3 Months Ended
	Mar. 31, 2018shares
Entity Registrant Name	Southcross Energy Partners, L.P.
Entity Central Index Key	1,547,638
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Smaller Reporting Company
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Common Units [Member]
Entity Common Stock, Shares Outstanding	48,636,517
Class B Convertible Units [Member]
Entity Common Stock, Shares Outstanding	18,982,577
Subordinated Units [Member]
Entity Common Stock, Shares Outstanding	12,213,713

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 3,013	$ 5,218
Trade accounts receivable	29,742	33,920
Due from Affiliate, Current	30,507	33,163
Prepaid expenses	2,136	2,592
Other current assets	8,184	497
Total current assets	73,582	75,390
Property, plant and equipment, net	901,354	914,547
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	108,702	111,747
Other assets	2,571	2,519
Total assets	1,086,209	1,104,203
Current liabilities:
Accounts payable and accrued liabilities	45,845	57,782
Due to Affiliate, Current	959	378
Other Long-term Debt, Current	4,256	4,256
Other current liabilities	17,045	12,976
Total current liabilities	68,105	75,392
Long-term Debt, Excluding Current Maturities	517,792	514,266
Other non-current liabilities	17,524	14,979
Total liabilities	603,421	604,637
Partners' capital:
Total partners' capital	482,788	499,566
Liabilities, preferred units, and partners' capital:
Total liabilities, preferred units and partners' capital	1,086,209	1,104,203
Limited Partner, units authorized
Partners' capital:
Total partners' capital	204,662	215,146
Class B Convertible Units [Member]
Partners' capital:
Total partners' capital	263,416	266,725
Subordinated Units [Member]
Partners' capital:
Total partners' capital	5,655	8,302
General Partner interest [Member]
Partners' capital:
General Partner interest	9,055	9,393
Total partners' capital	$ 9,055	$ 9,393

CONDENSED CONSOLIDATED BALANCE3

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - shares	12 Months Ended
	Dec. 31, 2017	Mar. 31, 2018
Limited Partner, units authorized
Partners' capital:
Limited Partner, units authorized	29,544,524	49,672,885
Limited Partner, units issued	48,502,090	48,538,451
Subordinated Units [Member]
Partners' capital:
Limited Partner, units authorized	12,213,713
Limited Partner, units outstanding	12,213,713	12,213,713
Preferred units issued
Temporary Equity, Shares Outstanding	1,769,915	0
Class B Convertible Units [Member] | Class B Convertible Units [Member]
Partners' capital:
Limited Partner, units outstanding		18,656,071
Conversion of Stock, Shares Issued	17,105,875

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues	$ 103,861	$ 114,387
Revenue from Related Parties	52,769	40,771
Total revenues (Note 10)	156,630	155,158
Expenses:
Cost of natural gas and liquids sold	123,517	118,691
Operations and maintenance	13,973	14,306
Depreciation and amortization	17,856	17,850
General and administrative	4,975	8,196
Asset Impairment Charges	0	649
Loss (gain) on sale of assets, net	0	(62)
Total expenses	160,321	159,630
Loss from operations	(3,691)	(4,472)
Income (Loss) from Equity Method Investments	(3,136)	(3,316)
Interest expense	(10,010)	(9,103)
Other Cost and Expense, Operating	(13,146)	(10,911)
Net loss	(16,837)	(15,383)
Net loss attributable to partners	(16,848)	(15,391)
Earnings per unit and distributions declared
Net loss allocated to limited partner, basic and diluted	(16,837)	(15,383)
Gain on insurance proceeds	0	1,500
General Partner [Member]
Expenses:
Net loss	(348)	(316)
General partner unit in-kind distribution	11	8
Earnings per unit and distributions declared
Net loss allocated to limited partner, basic and diluted		(308)
Common Limited Partners [Member]
Earnings per unit and distributions declared
Net loss allocated to limited partner, basic and diluted	$ (10,112)	$ (9,380)
Weighted average number of limited partner units outstanding, basic and diluted	48,627	48,522
Basic and diluted loss per unit (in dollars per unit)	$ (0.21)	$ (0.19)
Subordinated Limited Partners [Member]
Earnings per unit and distributions declared
Net loss allocated to limited partner, basic and diluted	$ (2,539)	$ (2,360)
Weighted average number of limited partner units outstanding, basic and diluted	12,214	12,214
Basic and diluted loss per unit (in dollars per unit)	$ (0.21)	$ (0.19)

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (16,837)	$ (15,383)

CONDENSED CONSOLIDATED STATEME6

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Proceeds from Issuance of Unsecured Debt	$ 15,000	$ 0
Cash flows from operating activities:
Net loss	(16,837)	(15,383)
Depreciation and amortization	17,856	17,850
Unit-based compensation	65	257
Other Noncash Expense	1,275	951
Gain (Loss) on Sale of Assets and Asset Impairment Charges	0	(62)
Unrealized gain on financial instruments	(5)	(17)
Income (Loss) from Equity Method Investments, Net of Dividends or Distributions	3,136	3,316
Asset Impairment Charges	0	649
Gain on insurance proceeds	0	(1,500)
Other Operating Activities, Cash Flow Statement	(63)	(285)
Changes in operating assets and liabilities:	6,836	11,257
Increase (Decrease) in Prepaid Expense and Other Assets	(7,225)	(630)
Increase (Decrease) in Other Noncurrent Assets	(65)	61
Increase (Decrease) in Accounts Payable and Accrued Liabilities	(11,274)	(12,099)
Increase (Decrease) in Other Operating Liabilities	5,386	(4,167)
Net Cash Provided by (Used in) Operating Activities	(915)	190
Net cash provided by operating activities
Capital expenditures	(3,423)	(7,553)
Proceeds from Contribution in Aid of Construction	108	505
Insurance proceeds from property damage claims, net of expenditures	0
Payments to Repair Property, Plant and Equipment, Less Insurance Proceeds		(2,000)
Net proceeds from sales of assets	0	143
Investment contributions to joint venture investments	(91)	(168)
Net cash used in investing activities	(3,406)	(5,073)
Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]
Repayments of Long-term Lines of Credit	(11,431)	(9,500)
Repayments of Long-term Debt	(1,064)	(2,161)
Borrowings under our credit facility	(126)	(122)
Financing costs	(255)	(74)
Payments Related to Tax Withholding for Share-based Compensation	(8)	(45)
Net Cash Provided by (Used in) Financing Activities	2,116	(11,902)
Net decrease in cash and cash equivalents	(2,205)	(16,785)
Cash and cash equivalents — Beginning of period	5,218	21,226
Cash and cash equivalents — End of period	$ 3,013	$ 4,441

CONDENSED CONSOLIDATED STATEME7

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN PARTNERS' CAPITAL - USD ($) $ in Thousands	Total	Common	CommonClass B Convertible Units [Member]	Class B Convertible Units [Member]	Class B Convertible Units [Member]Class B Convertible Units [Member]	Subordinated	SubordinatedClass B Convertible Units [Member]	SubordinatedSubordinated Units [Member]	General Partner [Member]	General Partner [Member]Class B Convertible Units [Member]	Common Units [Member]Common
Increase (Decrease) in Shareholders' Equity
Total partners' capital	$ 563,629	$ 255,124		$ 278,508		$ 19,240			$ 10,757
Net loss	(15,383)			(3,335)					(316)
Net loss allocated to limited partner, basic and diluted	(15,383)	(9,380)		(3,335)		(2,360)		$ (2,360)	(308)		$ (9,380)
Series A convertible preferred unit in-kind distribution and fair value adjustment			$ 315	(404)	$ (404)		$ 79			$ 10
Class B Convertible unit in-kind distribution		5		2		1			(8)
Retention bonus funded by Holdings		2,190
Partners' Capital Account, Unit-based Compensation	257	257
Payments Related to Tax Withholding for Share-based Compensation	(45)	(45)
Total partners' capital	550,648	247,826		275,575		16,800			10,447
Total partners' capital	499,566	215,146		266,725		8,302			9,393
Net loss	(16,837)			(3,849)					(348)
Payments of Stock Issuance Costs									337
Net loss allocated to limited partner, basic and diluted	(16,837)	(10,112)		(3,849)		(2,539)		$ (2,539)			$ (10,112)
Series A convertible preferred unit in-kind distribution and fair value adjustment			$ 422		$ (542)		$ 106			$ 14
Class B Convertible unit in-kind distribution		7		2		2			(11)
Equity contribution from Holdings	2	0							2
Retention bonus funded by Holdings		0
Partners' Capital Account, Unit-based Compensation	65	65
Payments Related to Tax Withholding for Share-based Compensation	(8)	(8)
Total partners' capital	$ 482,788	$ 204,662		$ 263,416		$ 5,655			$ 9,055

ORGANIZATION AND DESCRIPTION OF

ORGANIZATION AND DESCRIPTION OF BUSINESS	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
ORGANIZATION AND DESCRIPTION OF BUSINESS	ORGANIZATION AND DESCRIPTION OF BUSINESS Organization Southcross Energy Partners, L.P. (the "Partnership," "Southcross," "we," "our" or "us") is a Delaware limited partnership formed in April 2012. Our common units are listed on the New York Stock Exchange under the symbol “SXE.” We are a master limited partnership, headquartered in Dallas, Texas, that provides natural gas gathering, processing, treating, compression and transportation services and access to NGL fractionation and transportation services. We also source, purchase, transport and sell natural gas and NGLs. Our assets are located in South Texas, Mississippi and Alabama and include two gas processing plants, one fractionation facility, one treating facility and gathering and transportation pipelines. Southcross Holdings LP, a Delaware limited partnership (“Holdings”), indirectly owns 100% of Southcross Energy Partners GP, LLC, a Delaware limited liability company and our General Partner (“General Partner”) (and therefore controls us), all of our subordinated and Class B convertible units and 54.5% of our common units. Our General Partner owns an approximate 2.0% interest in us and all of our incentive distribution rights. EIG Global Energy Partners, LLC (“EIG”) and Tailwater Capital LLC (“Tailwater”) (collectively, the “Sponsors”) each indirectly own approximately one-third of Holdings, and a group of consolidated lenders under Holdings' term loan (the "Lenders") own the remaining one-third of Holdings. The AMID Transactions Contribution Agreement. On October 31, 2017, we and our General Partner entered into an Agreement and Plan of Merger (“Merger Agreement”) with American Midstream Partners, LP (“AMID”), American Midstream GP, LLC, the general partner of AMID (“AMID GP”), and a wholly-owned subsidiary of AMID (“Merger Sub”). The Merger Agreement provides that we will be merged with Merger Sub (the “Merger”), with the Partnership surviving the merger as a wholly-owned subsidiary of AMID. Simultaneously with the execution of the Merger Agreement, on October 31, 2017, AMID and AMID GP entered into a Contribution Agreement (the “Contribution Agreement”) with Holdings. Upon the terms and subject to the conditions set forth in the Contribution Agreement, Holdings will contribute its equity interests in a new wholly-owned subsidiary, which will hold substantially all the current subsidiaries (Southcross Holdings Intermediary LLC, a Delaware limited liability company, Southcross Holdings Guarantor GP LLC, a Delaware limited liability company, and Southcross Holdings Guarantor LP, a Delaware limited partnership, which in turn directly or indirectly own 100% of the limited liability company interest of our General Partner and 54.5% of the Partnership’s common units) and business of Holdings, to AMID and AMID GP in exchange for (i) the number of common units representing limited partner interests in AMID (each an “AMID Common Unit”) equal to $185,697,148 , subject to certain adjustments for cash, indebtedness, working capital and transaction expenses contemplated by the Contribution Agreement, divided by $13.69 , (ii) 4.5 million million new Series E convertible preferred units of AMID (the “AMID Preferred Units”), (iii) options to acquire 4.5 million AMID Common Units (the “Options”), and (iv) 15% of the equity interest in AMID GP (the transactions contemplated thereby and the agreements ancillary thereto, the “Contribution” and, together with the Merger, the “Transaction”). The Contribution Agreement contains customary representations and warranties and covenants by each of the parties. Holdings has also undertaken several additional obligations under the Contribution Agreement with respect to the Partnership and our subsidiaries. These include, without limitation, Holdings’ indemnification of AMID for certain obligations with respect to breaches of representations and warranties regarding the Partnership and our subsidiaries. In addition, Holdings is indemnifying AMID for certain contingent liabilities of the Partnership and our subsidiaries, including several ongoing litigation matters. A portion of the consideration, including approximately $25 million of the AMID Common Units to be received by Holdings will be deposited into escrow in order to secure the potential indemnification obligations until the longer of the end of 12 months from the closing of the Contribution Agreement, May 31, 2019 or the final resolution of the Special Indemnity Matters (as defined in the Contribution Agreement). In addition, all of the AMID Common Units, AMID Preferred Units and the Options received by Holdings as consideration under the Contribution Agreement will be subject to a lock-up agreement whereby such securities will be locked up until the longer of 12 months (with respect to the AMID Common Units) and 24 months (with respect to the AMID Preferred Units and Options) and, together with the AMID GP equity interests, the final resolutions of the Special Indemnity Matters (as defined in the Contribution Agreement). Further, during this time, cash distributions made by AMID or AMID GP to Holdings will be restricted, must remain within Holdings, and will be subject to recapture by AMID. The closing under the Contribution Agreement is conditioned upon, among other things: (i) expiration or termination of any applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the”HSR Act”), which was received on December 8, 2017, (ii) the absence of certain legal impediments prohibiting the transactions and (iii) with respect to AMID’s obligation to close only, the conditions precedent contained in the Merger Agreement having been satisfied and the Merger having become effective substantially concurrently with the closing of the Contribution Agreement. The Contribution Agreement contains provisions granting both parties the right to terminate the Contribution Agreement for certain reasons. The Contribution Agreement further provides that, upon termination by Holdings of the Contribution Agreement in the event of a Funding Failure (as defined in the Contribution Agreement), AMID may be required to pay a reverse termination fee in an amount up to $17 million . Merger Agreement . On October 31, 2017, we and our General Partner entered into the Merger Agreement with AMID and AMID GP. At the effective time of the Merger, each common unit of the Partnership issued and outstanding or deemed issued and outstanding as of immediately prior to the effective time, will be converted into the right to receive 0.160 (the “Exchange Ratio”) of an AMID Common Unit, except for those common units held by affiliates of the Partnership and our General Partner, which will be cancelled for no consideration. Each of our common units, subordinated units and Class B Convertible Units held by Holdings, or any of its subsidiaries, issued and outstanding as of the effective time, will be canceled for no consideration in connection with the closing of the Merger. The incentive distributions rights held by our General Partner outstanding immediately prior to the effective time will be cancelled for no consideration in connection with the closing of the Merger. Completion of the Merger is subject to the satisfaction of customary closing conditions, including (i) receipt of required regulatory approvals in connection with the Merger, including the expiration or termination of any applicable waiting period under the HSR Act and effectiveness of a registration statement on Form S-4 registering the AMID Common Units to be issued in connection with the Merger, (ii) the absence of certain legal impediments prohibiting the Merger Agreement and the transactions contemplated thereby, (iii) the closing of the Contribution in accordance with the terms of the Contribution Agreement and (iv) holders of at least a majority of our outstanding common units that are not held by our General Partner or its affiliates, holders of at least a majority of the outstanding subordinated units, voting as a class, and holders of at least a majority of the Class B Convertible Units, voting as a class, for the approval of the Merger Agreement and the transactions contemplated thereby. The Merger Agreement contains customary termination rights for both the Partnership and AMID. The Merger Agreement further provides that, upon termination of the Merger Agreement, under certain specified circumstances, the Partnership may be required to reimburse AMID’s expenses, subject to certain limitations, up to $0.5 million (“AMID Expenses”) or to pay AMID a termination fee of $2.0 million less any previous AMID expenses reimbursed by the Partnership (the “Termination Fee”). Letter Agreement. In connection with the Merger Agreement and Contribution Agreement, Holdings and the Partnership entered into a Letter Agreement (the “Letter Agreement”) providing that Holdings will reimburse the Partnership for all fees or expenses of the Partnership in connection with the Merger Agreement including (i) any fees or expenses of counsel, accountants, investment bankers and consultants retained by the Partnership or the conflicts committee of the Partnership, and (ii) the payment of any Termination Fee or the reimbursement of any AMID Expense, in each case, if the Merger has not closed and (a) the Merger Agreement is terminated because the Contribution Agreement has been terminated under certain specified circumstances or (b) the Merger Agreement is terminated without the prior approval of the conflicts committee of the Partnership under certain specified circumstances. On November 28, 2017, AMID and the Partnership filed Notification and Report Forms with the Antitrust Division of the Department of Justice and the Federal Trade Commission. On December 8, 2017, AMID and the Partnership received early termination of the applicable waiting period under the HSR Act. On January 11, 2018, AMID filed with the Securities Exchange Commission (the “SEC”) a Registration Statement on Form S-4 (file no. 333-222501) that includes a Proxy Statement of the Partnership and a Prospectus of AMID (the “Proxy Statement”). The S-4 was declared effective by the SEC on February 12, 2018, and the Proxy Statement was mailed to unitholders of the Partnership on or about February 14, 2018. On March 27, 2018, the Partnership held a special meeting of its unitholders (the “Special Meeting”) to consider and vote on proposals (i) to adopt and approve the Merger Agreement, and the transactions contemplated thereby, including the Merger, and (ii) to approve, on an advisory (non-binding) basis, the compensation that may be paid or become payable to the named executives officers of our General Partner in connection with the Merger. At the Special Meeting, our unitholders approved the Merger Agreement and the transactions contemplated thereby, including the Merger, and approved the Merger related executive compensation. Liquidity Consideration Our future cash flow will be materially adversely affected if the prices for natural gas, NGL and crude oil continue to affect the drilling for oil or natural gas in our primary operating area, the Eagle Ford Shale. The majority of our revenue is derived from fixed-fee and fixed-spread contracts, which have limited direct exposure to commodity price levels since we are paid based on the volumes of natural gas that we gather, process, treat, compress and transport and the volumes of NGLs we fractionate and transport, rather than being paid based on the value of the underlying natural gas or NGLs. In addition, a portion of our contract portfolio contains minimum volume commitment arrangements. The majority of our volumes are dependent upon the level of producer drilling activity. We remain focused on our efforts to improve future liquidity, and continue our cost-saving efforts to lower our operating and general and administrative cost structure. Additionally, we have explored various strategic options resulting in the execution of the Merger Agreement and Contribution Agreement. On December 29, 2016, we entered into the fifth amendment (the “Fifth Amendment”) to the Third Amended and Restated Revolving Credit Agreement with Wells Fargo, N.A., UBS Securities LLC, Barclays Bank PLC and a syndicate of lenders (the "Third A&R Revolving Credit Agreement"), pursuant to which, (i) the total aggregate commitments under the Third A&R Revolving Credit Agreement were reduced from $200 million to $125 million (then further reduced to $120 million on June 30, 2018) and the sublimit for letters of credit also was reduced from $75 million to $50 million (total aggregate commitments will be periodically further reduced through December 31, 2018); (ii) the Consolidated Total Leverage Ratio and Consolidated Senior Secured Leverage Ratio (each as defined in the Fifth Amendment) financial covenants were suspended until the quarter ending March 31, 2019; and (iii) the Consolidated Interest Coverage Ratio (as defined in the Fifth Amendment) financial covenant requirement was reduced from 2.50 to 1.00 to 1.50 to 1.00 for all periods ending on or prior to December 31, 2018 (the “Ratio Compliance Date”). Prior to the Ratio Compliance Date, we are required to maintain minimum levels of Consolidated EBITDA (as defined in the Fifth Amendment) on a quarterly basis and are subject to certain covenants and restrictions related to liquidity and capital expenditures. See Note 5. In connection with the execution of the Fifth Amendment, on December 29, 2016, the Partnership entered into (i) an Investment Agreement (the "Investment Agreement") with Holdings and Wells Fargo Bank, N.A., (ii) a Backstop Agreement (the "Backstop Agreement") with Holdings, Wells Fargo Bank, N.A. and the Sponsors and (iii) a First Amendment to Equity Cure Contribution Agreement (the "Equity Cure Contribution Amendment") with Holdings. Pursuant to the Equity Cure Contribution Amendment, on December 29, 2016, Holdings contributed $17.0 million to us in exchange for 11,486,486 common units. The proceeds of the $17.0 million contribution were used to pay down the outstanding balance under the Third A&R Revolving Credit Agreement and for general corporate purposes. In addition, on January 2, 2018, we notified Holdings that a Full Investment Trigger (as defined in the Investment Agreement) occurred on December 31, 2017. Pursuant to the Backstop Agreement, on January 2, 2018, Holdings delivered a Backstop Demand (as defined in the Investment Agreement) for each Sponsor to fund their respective pro rata portions of the Sponsor Shortfall Amount (as defined in the Investment Agreement) of $15.0 million in accordance with the Backstop Agreement. As consideration for the amount provided directly to us by the Sponsors pursuant to the Backstop Agreement, we issued to the Sponsors senior unsecured notes of the Partnership in an aggregate principal amount of $15.0 million (each, an "Investment Note" and collectively, the “Investment Notes”). The Investment Notes mature on November 5, 2019 and bear interest at a rate of 12.5% per annum. Interest on the Investment Notes shall be paid in kind (other than with respect to interest payable (i) on or after the maturity date, (ii) in connection with prepayment, or (iii) upon acceleration of the Investment Note, which shall be payable in cash); provided that all interest shall be payable in cash on or after December 31, 2018. The Investment Notes are the unsecured obligation of the Partnership subordinate in right of payment to any of our secured obligations under the Third A&R Revolving Credit Agreement. We continue to face a challenging corporate capital structure with substantial financial leverage and we remain focused on our overall profitability, including managing Partnership-wide, cost-savings initiatives. During management's ongoing assessment of the Partnership's financial forecast, the board of directors of Southcross Holdings GP, LLC (the “Holdings GP Board”) and the board of directors of our General Partner (the “SXE GP Board”), together with our management, determined that in our current corporate capital structure and absent continued access to equity cures from our Sponsors or a significant equity infusion from a third party, which the Partnership may not be able to obtain, or absent additional amendments to its Third A&R Revolving Credit Agreement or waivers of the March 31, 2019 requirement to comply with the Consolidated Total Leverage Ratio (as defined in the Fifth Amendment), the Partnership will not be able to comply with such financial covenant, which will trigger an event of default under the Senior Credit Facilities (as defined in Note 5). As a result of the Partnership’s expected inability to comply with its financial covenants twelve months from the issuance of this Form 10-Q, management has determined that there are conditions and events that raise substantial doubt about the Partnership’s ability to continue as a going concern. If the Partnership's independent registered public accounting firm reports in a subsequent audit report the existence of substantial doubt regarding the Partnership's ability to continue as a going concern, this would lead to an event of default under the Senior Credit Facilities which, in turn, would trigger a cross default of Southcross Holdings Borrowers’ credit facilities. Such events of default, if not cured, would allow the lenders under each of these borrowing arrangements to accelerate the maturity of the debt, making it due and payable immediately. On October 31, 2017, we and our General Partner entered into the Merger Agreement, which provides that we will be merged with Merger Sub with the Partnership surviving the Merger as a wholly-owned subsidiary of AMID. As a condition to the closing of the Merger, AMID is required to repay all of the outstanding debt of the Partnership and Holdings. Upon completion of the Merger and the payoff of such debt, the conditions and events that have caused the existence of substantial doubt described above will be eliminated. Should the Merger Agreement not close, management plans to pursue all available options to generate liquidity and maintain compliance with the Partnership’s financial covenants and other commitments including refinancing its indebtedness and negotiating with its lenders for more favorable terms. Management cannot reasonably assure that it will be effective in implementing any such strategy, and consequently, has concluded that substantial doubt exists regarding SXE’s ability to continue as a going concern.

BASIS OF PRESENTATION AND SUMMA

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Basis of Presentation We prepared this report under the rules and regulations of the SEC and in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial statements. Accordingly, these condensed consolidated financial statements do not include all of the disclosures required by GAAP and should be read in conjunction with our 2017 Annual Report on Form 10-K (“ 2017 Annual Report on Form 10-K”). The condensed consolidated financial statements as of March 31, 2018 and December 31, 2017 , and for the three months ended March 31, 2018 and 2017 , are unaudited and have been prepared on the same basis as the audited financial statements included in our 2017 Annual Report on Form 10-K. However, on January 1, 2018, the Partnership adopted Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606) (“ASC 606”), using the modified retrospective method. Accordingly, our condensed consolidated financial statements for the three months ended March 31, 2018 have been prepared in accordance with the updated accounting principles under the new standard. Adjustments (consisting of normal recurring adjustments) necessary for a fair presentation of the results of operations and financial position have been included herein. All intercompany accounts and transactions have been eliminated in the preparation of the accompanying condensed consolidated financial statements. The accompanying unaudited condensed consolidated financial statements were prepared in conformity with GAAP, which requires management to make various estimates and assumptions that may affect the amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the applicable period. Actual results may differ from those estimates. Information for interim periods may not be indicative of our operating results for the entire year. We evaluate events that occur after the balance sheet date, but before the financial statements are issued, for potential recognition or disclosure. Based on the evaluation, we determined that there were no material subsequent events for recognition or disclosure other than those disclosed in this report. See Note 13. The condensed consolidated statement of cash flows for the three months ended March 31, 2017, has been reclassified for consistency with the current period presentation for aid-in-construction payment receipts. Beginning in the second quarter of 2017, and continuing throughout the rest of 2017, we reclassified payments for aid-in-construction projects to a separate line item. Previously, such payments were included in the capital expenditures line item. Aid-in-construction projects refer to certain capital projects in which third parties are obligated to reimburse us for all or a portion of the project expenditures. Segments Our chief operating decision-maker is the Chief Executive Officer who reviews financial information presented on a consolidated basis in order to assess our performance and make decisions about resource allocations. There are no segment managers who are held accountable by the chief operating decision-maker, or anyone else, for operations, operating results and planning for levels or components below the consolidated unit level. Accordingly, we have determined that we have one reportable segment. Significant Accounting Policies During the three months ended March 31, 2018 , the Partnership adopted ASC 606. As a result, there was a change to our significant accounting policies described in Note 1 of our 2017 Annual Report on Form 10-K, as described below. On December 22, 2017, the Tax Cuts and Jobs Act was signed into law and made significant changes to the U.S. Internal Revenue Code. Such changes include a reduction in the corporate and individual tax rates and limitations on certain deductions and credits, among other changes. This will not have a material impact to our ongoing business operations. Adopted Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued ASC 606, which is a comprehensive new revenue recognition standard that superseded substantially all existing revenue recognition guidance under GAAP. The standard's core principle is that a company will recognize revenue when it transfers promised goods or services to customers and in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. Since 2014, the FASB has issued a series of accounting pronouncements that update the identifying performance obligations and licensing implementation guidance. The Partnership implemented ASC 606 effective on January 1, 2018, applying ASC 606 to customer contracts which were not completed as of the effective date, using the modified retrospective method of adoption. As a result, we anticipate the timing of our revenue to remain the same with respect to the majority of our contracts. Under the new standard, we identified certain natural gas purchase contracts that contained fees which were previously recognized as revenue for services provided to producers. Beginning on January 1, 2018, the fee revenue which previously was presented within revenue is now presented within the costs of natural gas and liquids sold line item within the condensed consolidated statement of operations. We also have certain natural gas sales contracts with customers whereby the customers provide certain aid-in-construction capital expenditure payments to us to construct pipelines on our operating assets which we own and operate. We previously accounted for these arrangements as a reduction to property, plant and equipment. Under the new standard, we reclassified these payments as deferred revenue on our condensed consolidated balance sheets at January 1, 2018, which resulted in a $2.7 million cumulative effect of accounting change being recorded to increase property, plant and equipment. The deferred revenue will be amortized over five years, the expected length of the contract. Recent Accounting Pronouncements Accounting standard-setting organizations frequently issue new or revised accounting pronouncements. We review and evaluate new pronouncements and existing pronouncements to determine their impact, if any, on our condensed consolidated financial statements. We are evaluating the impact of each pronouncement on our condensed consolidated financial statements. In February 2016, the FASB issued a pronouncement amending disclosure and presentation requirements for lessees and lessors on the face of the balance sheet. The pronouncement states that a lessee should recognize a liability to make lease payments and a right-of-use asset representing its right to use the underlying asset for the lease term. When measuring assets and liabilities arising from a lease, a lessee (and a lessor) should include payments to be made in optional periods only if the lessee is reasonably certain to exercise an option to extend the lease or not to exercise an option to terminate the lease. Similarly, optional payments to purchase the underlying asset should be included in the measurement of lease assets and lease liabilities only if the lessee is reasonably certain to exercise that purchase option. In addition, also consistent with the previous leases guidance, a lessee (and a lessor) should exclude most variable lease payments in measuring lease assets and lease liabilities, other than those that depend on an index or a rate or are in substance fixed payments. In January 2018, the FASB issued an updated accounting pronouncement which permits an entity to elect an optional transition practical expedient to not evaluate land easements that exist or expired before the entity’s adoption of the new leasing standard and that were not previously accounted for as leases. The lease pronouncement will become effective beginning in 2019.

NET (LOSS) INCOME PER LIMITED P

NET (LOSS) INCOME PER LIMITED PARTNER UNIT AND DISTRIBUTIONS	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
NET LOSS PER LIMITED PARTNER UNIT AND DISTRIBUTIONS	NET LOSS PER LIMITED PARTNER UNIT AND DISTRIBUTIONS Net Loss Per Limited Partner Unit The following is a reconciliation of net loss attributable to limited partners and the limited partner units used in the basic and diluted earnings per unit calculations for the three months ended March 31, 2018 and 2017 (in thousands, except unit and per unit data): Three Months Ended March 31, 2018 2017 Net loss $ (16,837 ) $ (15,383 ) General partner unit in-kind distribution (11 ) (8 ) Net loss attributable to partners $ (16,848 ) $ (15,391 ) General partner's interest (1) $ (348 ) $ (316 ) Class B Convertible limited partner interest (1) (3,849 ) (3,335 ) Limited partners' interest (1) Common $ (10,112 ) $ (9,380 ) Subordinated (2,539 ) (2,360 ) (1) General Partner's and limited partners’ interests are calculated based on the allocation of net losses for the period, net of the General Partner unit in-kind distributions. The Class B Convertible Unit interest is calculated based on the allocation of only net losses for the period. Three Months Ended March 31, Common Units 2018 2017 Interest in net loss $ (10,112 ) $ (9,380 ) Effect of dilutive units - numerator (1) — — Dilutive interest in net loss $ (10,112 ) $ (9,380 ) Weighted-average units - basic 48,626,521 48,521,512 Effect of dilutive units - denominator (1) — — Weighted-average units - dilutive 48,626,521 48,521,512 Basic and diluted net loss per common unit $ (0.21 ) $ (0.19 ) Three Months Ended March 31, Subordinated Units 2018 2017 Interest in net loss $ (2,539 ) $ (2,360 ) Effect of dilutive units - numerator (1) — — Dilutive interest in net loss $ (2,539 ) $ (2,360 ) Weighted-average units - basic 12,213,713 12,213,713 Effect of dilutive units - denominator (1) — — Weighted-average units - dilutive 12,213,713 12,213,713 Basic and diluted net loss per subordinated unit $ (0.21 ) $ (0.19 ) (1) Because we had a net loss for all periods for common units and the subordinated units, the effect of the dilutive units would be anti-dilutive to the per unit calculation. Therefore, the weighted average units outstanding are the same for basic and dilutive net loss per unit for those periods. The weighted average units that were not included in the computation of diluted per unit amounts were 215,878 and 89,089 unvested awards granted under the LTIP for the three months ended March 31, 2018 and 2017, respectively. Our calculation of the number of weighted-average units outstanding includes the common units that have been awarded to our directors that are deferred under our Non-Employee Director Deferred Compensation Plan (the “Plan”). In connection with the execution of the Merger Agreement, the board of directors of our General Partner approved an amendment (the “Amendment”) to the Plan. In connection with and pursuant to the terms of the Merger Agreement, the Partnership is required to terminate the Plan and liquidate the sole participant’s account within 30 days prior to the closing of the Merger. The Amendment terminates the Plan effective as of one business day prior to the closing of the Merger and provides that the participant’s account will be liquidated and paid to the participant or his beneficiary, if applicable, in the form of a lump sum cash payment as soon as practical following the effective time of the Merger. The Amendment will be null and void in the event that the closing of the Merger does not occur. Cash Distributions Our agreement of limited partnership (as amended and restated, the “Partnership Agreement”), requires that within 45 days after the end of each quarter, we distribute all of our available cash to unitholders of record on the applicable record date, as determined by our General Partner. There is no guarantee that we will pay the minimum quarterly distribution on our units in any quarter. Beginning with the third quarter of 2014, until such time that we have a distributable cash flow divided by cash distributions ratio (“Distributable Cash Flow Ratio”) of at least 1.0 , Holdings, the indirect holder of all of our subordinated units, waived the right to receive distributions on any subordinated units that would cause the Distributable Cash Flow Ratio to be less than 1.0 . More importantly, the First Amendment (as defined in Note 5) imposed additional restrictions on our ability to declare and pay quarterly cash distributions with respect to our subordinated units. Additionally, we are restricted under the Fifth Amendment from paying a distribution with respect to our common units until our Consolidated Total Leverage Ratio is below 5.0 . See Note 5. The SXE GP Board suspended paying a quarterly distribution with respect to the fourth quarter of 2015, every quarter of 2016 and 2017 and the first quarter of 2018 to conserve any excess cash for the operation of our business. The SXE GP Board and our management believe this suspension to be in the best interest of our unitholders and will continue to evaluate our ability to reinstate the distribution in future periods. More importantly, we are restricted under the terms of the Fifth Amendment from paying a distribution until our Consolidated Total Leverage Ratio is below 5.0 and we are also restricted from paying such distribution under the terms of the Merger Agreement. Paid In-Kind Distributions Class B Convertible Units. As of March 31, 2018 , the Class B Convertible Units consisted of 18,656,071 of such units including the additional Class B Convertible Units issued in-kind as a distribution (“Class B PIK Units”). The Class B Convertible Units are not participating securities for purposes of the earnings per unit calculation. Commencing with the quarter ended September 30, 2014 and until converted, as long as certain requirements are met, the holders of the Class B Convertible Units will receive quarterly distributions in an amount equal to $0.3257 per unit. These distributions will be paid quarterly in Class B PIK Units within 45 days after the end of each quarter. Our General Partner was entitled, and has exercised its right, to retain its 2.0% general partner interest in us in connection with the original issuance of the Class B Convertible Units. In connection with future distributions of Class B PIK Units, the General Partner is entitled to a corresponding distribution to maintain its 2.0% general partner interest in us. The Class B Convertible Units have the same rights, preferences and privileges, and are subject to the same duties and obligations, as our common units, with certain exceptions. See Note 7. The following table represents the Class B PIK unit distribution paid on the Class B Convertible Units for the periods ended December 31, 2017 and March 31, 2018 (in thousands, except per unit and in-kind distribution units): Payment Date Attributable to the Quarter Ended Per Unit Distribution In-Kind Class B Convertible Unit In-Kind Class B Convertible Distributions (1) In-Kind Unit to General Partner In-Kind General Partner Distribution Value (1) 2018 May 3, 2018 March 31, 2018 $ 0.3257 $ 326,506 $ 532 $ 6,663 $ 11 2017 February 9, 2018 December 31, 2017 $ 0.3257 320,890 $ 542 6,549 $ 11 November 11, 2017 September 30, 2017 0.3257 315,370 741 6,436 15 August 11, 2017 June 30, 2017 0.3257 309,946 983 6,325 20 May 11, 2017 March 31, 2017 0.3257 304,615 1,060 6,216 22 (1) The fair value was calculated as required, based on the common unit price at the quarter end date for the period attributable to the distribution, multiplied by the number of units distributed.

FINANCIAL INSTRUMENTS

FINANCIAL INSTRUMENTS	3 Months Ended
	Mar. 31, 2018
Investments, All Other Investments [Abstract]
FINANCIAL INSTRUMENTS	FINANCIAL INSTRUMENTS Fair Value Measurements We apply recurring fair value measurements to our financial assets and liabilities. In estimating fair value, we generally use a market approach and incorporate assumptions that market participants would use in pricing the asset or liability, including assumptions about risk and/or the risks inherent in the inputs to the valuation techniques. The fair value measurement inputs we use vary from readily observable inputs that represent market data obtained from independent sources to unobservable inputs that reflect our own market assumptions that cannot be validated through external pricing sources. Based on the observability of the inputs used in the valuation techniques, the financial assets and liabilities carried at fair value in the financial statements are classified as follows: • Level 1—Represents unadjusted quoted market prices in active markets for identical assets or liabilities that are accessible at the measurement date. This category primarily includes our cash and cash equivalents. • Level 2—Represents quoted market prices for similar assets or liabilities in active markets, quoted market prices in markets that are not active or other inputs that are observable or can be corroborated by observable market data. This category primarily includes variable rate debt, over-the-counter swap contracts based upon natural gas price indices and interest rate derivative transactions. • Level 3—Represents derivative instruments whose fair value is estimated based on internally developed models and methodologies utilizing significant inputs that are generally less readily observable from market sources. We do not have financial assets and liabilities classified as Level 3. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, the level in the fair value hierarchy must be determined based on the lowest level input that is significant to the fair value measurement. An assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and consideration of factors specific to the asset or liability. The carrying amounts of cash and cash equivalents, accounts receivable and accounts payable represent fair values based on the short-term nature of these instruments. The fair value of our Credit Facility (defined in Note 5) approximates its carrying amount due primarily to the variable nature of the interest rate of the instrument and is considered a Level 2 fair value measurement. As of March 31, 2018, the fair value of our term loan was $426.9 million and the fair value of the Investment Notes (defined in Note 5) was $15.2 million , based on recent trading levels and are considered Level 2 fair value instruments. Derivative Financial Instruments Interest Rate Derivative Transactions We enter into interest rate cap contracts to limit our London Interbank Offered Rate (“LIBOR”) based interest rate risk on the portion of debt hedged at the contracted cap rate. Our interest rate cap position was as follows (in thousands): Estimated Fair Value Notional Amount Cap Rate Effective Date Maturity Date March 31, 2018 50,000 3.000 % June 30, 2016 June 30, 2018 — 40,000 3.000 % December 31, 2016 January 1, 2018 — 40,000 3.000 % December 31, 2016 July 1, 2018 — 40,000 3.000 % December 31, 2016 January 1, 2019 — 60,000 3.000 % June 30, 2017 June 30, 2019 7 85,000 3.000 % December 31, 2017 June 30, 2018 — $ 7 These interest rate derivatives are not designated as cash flow hedging instruments for accounting purposes and as a result, changes in the fair value are recognized in interest expense immediately. The fair value of our interest rate derivative transactions is determined based on a discounted cash flow method using contractual terms of the transactions. The floating coupon rate is based on observable rates consistent with the frequency of the interest cash flows. We have elected to present our interest rate derivatives net in the balance sheets. There was no effect of offsetting in the balance sheets as of March 31, 2018 or December 31, 2017 . The fair values of our interest rate derivative transactions were as follows (in thousands): Significant Other Observable Inputs (Level 2) Fair Value Measurement as of March 31, 2018 December 31, 2017 Current interest rate derivative assets $ 6 $ 1 Non-current interest rate derivative assets 1 1 Total interest rate derivatives $ 7 $ 2 The realized and unrealized amounts recognized in interest expense associated with derivatives were as follows (in thousands): Three Months Ended March 31, 2018 2017 Unrealized loss (gain) on interest rate derivatives $ (5 ) $ 2 Realized gain on interest rate derivatives — (15 )

LONG-LIVED ASSETS

LONG-LIVED ASSETS	3 Months Ended
	Mar. 31, 2018
Property, Plant and Equipment [Abstract]
LONG-LIVED ASSETS	LONG-LIVED ASSETS Property, Plant and Equipment Property, plant and equipment consisted of the following (in thousands): Estimated Useful Life (yrs) March 31, 2018 December 31, 2017 Pipelines 15-30 $ 571,730 $ 571,730 Gas processing, treating and other plants 15 520,480 520,765 Compressors 5-15 78,997 78,997 Rights of way and easements 15 49,897 49,897 Furniture, fixtures and equipment 5 9,746 9,746 Capital lease vehicles 3-5 2,315 2,114 Total property, plant and equipment 1,233,165 1,233,249 Accumulated depreciation and amortization (352,223 ) (334,528 ) Total 880,942 898,721 Construction in progress 6,759 2,173 Land and other 13,653 13,653 Property, plant and equipment, net $ 901,354 $ 914,547 Depreciation is provided using the straight-line method based on the estimated useful life of each asset. Depreciation expense for the three months ended March 31, 2018 and 2017, was $17.9 million , respectively. As part of Partnership-wide, cost-saving initiatives, management elected to idle the Bonnie View fractionation facility (“Bonnie View”) in the second quarter of 2017. As a result, all of our Y-grade product is being sold to Holdings in accordance with our affiliate Y-grade sales agreement and is being fractionated at the Holdings’ Robstown fractionation facility (“Robstown”). We utilize Bonnie View as a backup option to the extent Robstown is unable to fractionate our Y-grade product. We received a settlement payment of $2.0 million from our insurance carriers in the first quarter of 2017 related to the fire at our Gregory facility in 2015, and recorded a $1.5 million gain related to insurance proceeds received in excess of expenditures incurred to repair the Gregory facility. As stipulated in the Term Loan Agreement (defined in Note 5), we used $1.0 million ( $2.0 million of proceeds, net of the 2015 insurance deductible of $0.5 million and additional expenditures to repair Gregory of $0.5 million ) of the proceeds to make a mandatory prepayment on our term loan. Intangible Assets Intangible assets of $1.3 million as of March 31, 2018 and December 31, 2017 , respectively, represent the unamortized value acquired to long-term supply and gathering contracts. These intangible assets are amortized on a straight-line basis over the 30 -year expected useful lives of the contracts through 2041. Amortization expense over the next five years related to intangible assets is not significant.

LONG-TERM DEBT

LONG-TERM DEBT	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
LONG-TERM DEBT	LONG-TERM DEBT Our outstanding debt and related information at March 31, 2018 and December 31, 2017 are as follows (in thousands): March 31, 2018 December 31, 2017 Revolving credit facility due 2019 $ 83,124 $ 94,555 Term loans due 2021 432,332 433,396 Senior unsecured notes payable due 2019 15,349 — Original issuance discount on term loans due 2021 (1,053 ) (1,134 ) Total long-term debt (including current portion) 529,752 526,817 Current portion of long-term debt (4,256 ) (4,256 ) Deferred financing costs (7,704 ) (8,295 ) Total long-term debt $ 517,792 $ 514,266 Outstanding letters of credit $ 25,061 $ 24,911 Remaining unused borrowings $ 16,815 $ 15,534 Three Months Ended March 31, 2018 2017 Weighted average interest rate 6.60 % 5.80 % Average outstanding borrowings $ 531,328 $ 553,699 Maximum borrowings $ 532,952 $ 553,805 Senior Credit Facilities Our long-term debt arrangements consist of (i) the Third A&R Revolving Credit Agreement and (ii) a Term Loan Credit Agreement with Wilmington Trust, National Association, UBS Securities LLC and Barclays Bank PLC and a syndicate of lenders (the “Term Loan Agreement” and, together with the Third A&R Revolving Credit Agreement, the “Senior Credit Facilities”). Substantially all of our assets are pledged as collateral under the Senior Credit Facilities, with the security interest of the facilities ranking pari passu. Third A&R Revolving Credit Agreement The Third A&R Revolving Credit Agreement is a five -year $200 million revolving credit facility due August 4, 2019 (the “Credit Facility”). Borrowings under our Credit Facility bear interest at the LIBOR plus an applicable margin or a base rate as defined in the Third A&R Revolving Credit Agreement. Pursuant to the Third A&R Revolving Credit Agreement, among other things: (a) the letters of credit sublimit was set at $75 million ; and (b) if we fail to comply with the Consolidated Total Leverage Ratio, Consolidated Senior Secured Leverage Ratio and the Consolidated Interest Coverage Ratio covenants (each as defined in the Third A&R Revolving Credit Agreement, and collectively the “Financial Covenants”) (each such failure, a “Financial Covenant Default”), we have the right (a limited number of times) to cure such Financial Covenant Default by having the Sponsors purchase equity interests in or make capital contributions to us resulting in, among other things, proceeds that, if added to Consolidated EBITDA (as defined in the Third A&R Revolving Credit Agreement) would result in us satisfying the Financial Covenants. Amendments to Third A&R Revolving Credit Agreement On May 7, 2015, we entered into the first amendment to our Third A&R Revolving Credit Agreement among the Partnership, as the borrower, the lenders and other parties thereto (the “First Amendment”). The First Amendment, among other things: (i) revised the maximum Consolidated Total Leverage Ratio set at 5.00 to 1.0 as of the last day of each fiscal quarter after September 30, 2016, without any step-ups in connection with acquisitions; (ii) increased the applicable margins used in connection with the loans and the commitment fee so that the applicable margin for Eurodollar Loans (as used in the Third A&R Revolving Credit Agreement) ranges from 2.00% to 4.50% , the applicable margin for base rate loans ranges from 1.00% to 3.50% and the applicable rate for commitment fees ranges from 0.375% to 0.500% ; and (iii) allowed us an unlimited number of quarterly equity cures related to our Financial Covenant Default through the fourth quarter of 2016, and no more than two in a twelve month period thereafter for the life of the agreement. Beginning on January 1, 2017, we are limited to no more than four equity cures, with no more than two in a twelve month period. On December 29, 2016, we entered into the Fifth Amendment which, among other things: (i) permitted a full waiver for all defaults or events of default arising out of our failure to comply with the financial covenant to maintain a Consolidated Total Leverage Ratio less than 5.00 to 1.00 for the quarter ended September 30, 2016; (ii) reduced the total aggregate commitments under the Third A&R Revolving Credit Agreement from $200 million to $145 million and reduced the sublimit for letters of credit from $75 million to $50 million . Total aggregate commitments was reduced to $125 million on March 31, 2018, and will be further reduced to $120 million on June 30, 2018 and $115 million on December 31, 2018 and will also be reduced in an amount equal to the net proceeds of any Permitted Note Indebtedness (as defined in the Fifth Amendment) we may incur in the future; (iii) modified the borrowings under the Third A&R Revolving Credit Agreement to bear interest at the LIBOR or a base rate plus an applicable margin that cumulatively increases pursuant to the Fifth Amendment by (a) 125 basis points if our Consolidated Total Leverage Ratio is greater than or equal to 5.00 to 1.00 , plus (b) 100 basis points if our Consolidated Total Leverage Ratio is greater than or equal to 6.00 to 1.00 , plus (c) 100 basis points if our Consolidated Total Leverage Ratio is greater than or equal to 7.00 to 1.00 , plus (d) 100 basis points if our Consolidated Total Leverage Ratio is greater than or equal to 8.00 to 1.00 . At our election, the 100 basis point increase to the applicable margin upon our Consolidated Total Leverage Ratio being greater than or equal to 8.00 to 1.00 may be replaced with a 150 basis point increase that is payable in kind; (iv) suspended the Consolidated Total Leverage Ratio and Consolidated Senior Secured Leverage Ratio financial covenants and reduced the Consolidated Interest Coverage Ratio financial covenant requirement from 2.50 to 1.00 to 1.50 to 1.00 for all periods ending on or prior to the Ratio Compliance Date; (v) requires us to generate Consolidated EBITDA in certain minimum amounts beginning with the quarter ending December 31, 2016 and rolling forward thereafter through the quarter ending December 31, 2018; (vi) requires us to maintain at least $3 million of Liquidity (as defined therein) as of the last business day of each calendar week; (vii) restricts our capital expenditures for growth and maintenance to not exceed certain amounts per fiscal year; and (viii) beginning with the fiscal quarter ending March 31, 2019, our Consolidated Total Leverage Ratio cannot exceed 5.00 to 1.00 and our Consolidated Senior Secured Leverage Ratio cannot exceed 3.50 to 1.00 . Until such time as our Consolidated Total Leverage Ratio is less than 5.00 to 1.00 , we will also be restricted from making cash distributions to our unitholders and from entering into acquisition or merger agreements with third-party businesses involving a purchase price greater than $10 million , unless such acquisition is funded entirely using the proceeds from the issuance of equity. In addition, until such time as our Consolidated Total Leverage Ratio is less than or equal to 5.00 to 1.00 , we will be required to repay any outstanding borrowings under the Credit Facility in an amount equal to 50% of our Excess Cash Flow (as defined in the Fifth Amendment). Our Consolidated Total Leverage Ratio was 8.64 to 1.00 as of March 31, 2018. Term Loan Agreement The Term Loan Agreement is a $450 million senior secured term loan facility maturing on August 4, 2021. Borrowings under our Term Loan Agreement bear interest at LIBOR plus 4.25% or a base rate as defined in the respective credit agreement with a LIBOR floor of 1.00% . The facility will amortize in equal quarterly installments in an aggregate amount equal to 1% of the original principal amount, less any mandatory prepayments (as defined in the Term Loan Agreement), $1.064 million , with the remainder due on the maturity date. Senior Unsecured Note On January 2, 2018, Holdings delivered a Backstop Demand (as defined in the Investment Agreement) for each Sponsor to fund their respective pro rata portions of the Sponsor Shortfall Amount (as defined in the Investment Agreement) of $15.0 million in accordance with the Backstop Agreement. As consideration for the amount contributed directly to us by a Sponsor pursuant to the Backstop Agreement, we issued to the Sponsors senior unsecured notes of the Partnership in an aggregate principal amount of $15.0 million (each, an "Investment Note" and collectively, the “Investment Notes”). The Investment Notes mature on November 5, 2019 and bear interest at a rate of 12.5% per annum. Interest on the Investment Note shall be paid-in-kind (“PIK”) (other than with respect to interest payable (i) on or after the maturity date, (ii) in connection with prepayment, or (iii) upon acceleration of the Investment Note, which shall be payable in cash); provided that all interest shall be payable in cash on or after December 31, 2018. The Investment Notes are the unsecured obligation of the Partnership subordinate in right of payment to any of our secured obligations under the Third A&R Revolving Credit Agreement. The senior unsecured note payable includes $0.3 million of PIK interest as of March 31, 2018. Deferred Financing Costs Deferred financing costs are capitalized and amortized as interest expense under the effective interest method over the term of the related debt. The unamortized balance of deferred financing costs is included in long-term debt in the balance sheets. Changes in deferred financing costs are as follows (in thousands): 2018 2017 Deferred financing costs, January 1 $ 8,295 $ 11,474 Capitalization of deferred financing costs 255 96 Amortization of deferred financing costs (846 ) (869 ) Deferred financing costs, March 31 $ 7,704 $ 10,701

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Legal Matters From time to time, we are party to certain legal or administrative proceedings that arise in the ordinary course and are incidental to our business. For example, during periods when we are expanding our operations through the development of new pipelines or the construction of new plants, we may become involved in disputes with landowners that are in close proximity to our activities. While we are involved currently in several such proceedings and disputes, our management believes that none of such proceedings or disputes will have a material adverse effect on our results of operations, cash flows or financial condition. However, future events or circumstances, currently unknown to management, will determine whether the resolution of any litigation or claims ultimately will have a material effect on our results of operations, cash flows or financial condition in any future reporting periods. TPL. On April 5, 2017, TPL SouthTex Processing Company, LP (“TPL”), an indirect subsidiary of Targa, filed a Demand for Arbitration with the American Arbitration Association, against FL Rich Gas Services, LP, an indirect subsidiary of the Partnership (“FL Rich”), related to the operation of T2 EF Cogeneration Holdings LLC (“T2 Cogen”). T2 Cogen, the owner of a cogeneration facility in South Texas, is operated by FL Rich pursuant to the terms of the Generation Plant Operating Agreement, dated March 4, 2013 (the “Operating Agreement”). TPL alleges that FL Rich (i) breached the Operating Agreement in its alleged failure to receive from the United States Environmental Protection Agency a Prevention of Significant Deterioration permit thereby harming Targa’s investment in T2 Cogen, (ii) breached its fiduciary duties with respect to funds or assets of T2 Cogen as operator of T2 Cogen under the terms of the Operating Agreement, and (iii) breached the Operating Agreement and the Limited Liability Company Agreement of T2 Cogen (the “LLC Agreement”) in installing a third turbine inside its Lone Star plant. TPL is seeking, among other things, (a) unspecified damages related to the alleged breaches under the Operating Agreement and the LLC Agreement, (b) the return of approximately $26 million in capital contributions to T2 Cogen received from TPL under the LLC Agreement and the Operating Agreement, and (c) the dissolution and liquidation of T2 Cogen and its assets, respectively. An arbitration hearing has been scheduled for August 2018 which we have requested to be rescheduled to September or October 2018. We believe this matter is without merit and we intend to defend the arbitration vigorously. Because this matter is in an early stage, we are unable to predict its outcome and the possible loss or range of loss, if any, associated with its resolution or any potential effect the matter may have on our financial position. Depending on the outcome or resolution of this matter, it could have a material effect on our financial position. Woodsboro . Our General Partner has been named as a defendant in a lawsuit filed on April 29, 2016 in Duval County, Texas styled Victor Henneke, Jr., et al. v. Southcross Energy Partners GP, LLC, et al., Cause No. DC-16-139, 229th Judicial District, Duval County, Texas (the “Henneke Case”). The Henneke Case involves claims by two employees of a third party contractor for personal injury and wrongful death resulting from the alleged negligence of the Partnership related to a pipeline construction project located at our Woodsboro processing facility. The Partnership’s insurance carriers are providing coverage to the Partnership under its general liability policy. No trial date has been set for the contractual liability claims in the case. A jury trial for the personal injury claims began in Duval County, Texas on September 18, 2017. On September 22, 2017, two different award amounts were determined by the jury, the first of which was determined prior to the jury being released by the judge and the second was determined after the jury was recalled by the judge. On April 25, 2018, the successor judge entered a judgment against Southcross in the amount of approximately $7.7 million . We are evaluating whether or not to appeal this judgment and believe that we have adequate insurance coverage to cover this matter. As a result, during the three months ended March 31, 2018, we recorded a $7.7 million liability and receivable from our insurance carrier related to the Woodsboro legal settlement. On April 27, 2018 and April 30, 2018, the plaintiffs filed two new lawsuits against Southcross CCNG Transmission Ltd. that allege the same or similar causes of actions for which we received judgements on in Duval County. The cases are styled as Ivy Gonzalez on behalf of M.R. Gonzalez and M.N. Gonzalez Minor Children vs. Southcross CCNG Transmission Ltd.; Gene Henneke as independent administrator of the estate of Dennis Henneke; Galbreath Contracting, Inc. and Severo Sepulveda, Jr. Cause no. DE-18-82 and Amy Gonzalez as co-personal representative of the estate of Jesus Gonzalez, Jr. under the Texas Survival Act and for and on behalf of wrongful death beneficiaries M.R. Gonzalez and M.N. Gonzalez Minor Children and Amy Gonzalez and Jesus Gonzalez, Sr. vs. Southcross CCNG Transmission Ltd.; Gene Henneke as independent administrator of the estate of Dennis Henneke; Galbreath Contracting, Inc. and Severo Sepulveda, Jr. Cause no. DE-18-83. We intend to defend vigorously these pending matters and believe we have adequate insurance coverage with respect to these matters. Merger Agreement. In connection with the Merger, five putative class actions were filed in the United States District Court for the Northern District of Texas. The actions were filed against multiple, different entities and individuals, including by way of example only and among others, the Partnership, our General Partner, Southcross Holdings, Holdings GP, AMID, AMID Merger Sub, and certain former and current members of our executive management and the Board of Directors of our General Partner. As of May 7, 2018, three of such actions have been dismissed. Those cases are: • Robinson Iglesias v. Southcross Energy Partners, L.P., Southcross Energy Partners GP, LLC, Southcross Holdings LP, Southcross Holdings GP LLC, Bruce A. Williamson, David W. Biegler, Andrew A. Cameron, Nicholas J. Caruso, Jason H. Downie, Wallace Henderson, Jerry W. Pinkerton, Cherokee Merger Sub LLC, and American Midstream Partners, LP , Civil Action No. 3:18-cv-00158-N. Dismissed on April 10, 2018. • Adrian Marshall v. Southcross Energy Partners, L.P., Southcross Energy Partners GP, LLC, Southcross Holdings LP, Southcross Holdings GP LLC, Bruce A. Williamson, David W. Biegler, Andrew A. Cameron, Nicholas J. Caruso, Jr., Jason H. Downie, Jerry W. Pinkerton, Randall S. Wade, Bret M. Allan, American Midstream Partners, LP, and Cherokee Merger Sub LLC , Civil Action No. 3:18-cv-00272-D. Dismissed on April 11, 2018. • Kristin Doller v. Southcross Energy Partners, L.P., Southcross Energy Partners GP, LLC, Southcross Holdings LP, Southcross Holdings GP LLC, David W. Biegler, Andrew A. Cameron, Nicholas J. Caruso, Jr., Jason H. Downie, Jerry W. Pinkerton, Randall S. Wade, and Bruce A. Williamson , Civil Action No. 3:18-cv-00291-N. Dismissed on April 10, 2018. The complaints generally allege, among other things, that the registration statement on Form S-4 (file no. 333-222501) is false and materially misleading and that the defendants have violated Sections 14(a) and 20(a) of the Securities Exchange Act of 1934 and Rule 14a-9 promulgated thereunder. Generally, the complaints seek class certification, injunctive relief, damages, declaratory relief, and attorney’s fees and court costs. The two remaining actions filed in the United States District Court for the Northern District of Texas are captioned as follows: • Anthony Franchi v. Southcross Energy Partners, L.P., Southcross Energy Partners GP, LLC, Bruce A. Williamson, David W. Biegler, Andrew A. Cameron, Nicholas J. Caruso, Jr., Jason H. Downie, Jerry W. Pinkerton, Randall S. Wade, American Midstream Partners, LP, American Midstream Partners GP, LLC, and Cherokee Merger Sub LLC , Civil Action No. 3:18-cv-00179-D. • Robert Johnson v. Southcross Energy Partners, L.P., Southcross Energy Partners GP, LLC, Southcross Holdings LP, Southcross Holdings GP LLC, Bruce A. Williamson, David W. Biegler, Andrew A. Cameron, Nicholas J. Caruso, Jr., Jason H. Downie, Jerry W. Pinkerton, Randall S. Wade , Civil Action No. 3:18-cv-00289-C All defendants deny any wrongdoing in connection with the proposed Transaction and plan to defend rigorously against all pending claims. Corpus Christi Alumina LLC v. Southcross Marketing Co. Ltd. (In re Sherwin Alumina Co., LLC) , Case No. 18-02024 (Bankr. S.D. Tex.) Corpus Christi Alumina LLC the assignee of Sherwin Alumina Company LLC is seeking to recover from our subsidiary Southcross Marketing Co. Ltd., up to $10 million for natural gas payments made to us prior to Sherwin’s 2016 bankruptcy. We believe this claim to be without merit and intend to defend vigorously this claim. We do not believe this to have a material effect on our financial position. Regulatory Compliance In the ordinary course of our business, we are subject to various laws and regulations. In the opinion of our management, compliance with current laws and regulations will not have a material effect on our results of operations, cash flows or financial condition. Leases Capital Leases We have vehicle leases that are classified as capital leases. The termination dates of the lease agreements vary from 2018 to 2019. We recorded amortization expense related to the capital leases of $0.1 million each for the three months ended March 31, 2018 and 2017, respectively. Capital leases entered into during the three months ended March 31, 2018 and 2017, were $0.3 million and $0.4 million , respectively. The capital lease obligation amounts included in the balance sheets were as follows (in thousands): March 31, 2018 December 31, 2017 Other current liabilities $ 463 $ 410 Other non-current liabilities 578 410 Total $ 1,041 $ 820 Operating Leases We maintain operating leases in the ordinary course of our business activities. These leases include those for office and other operating facilities and equipment. The termination dates of the lease agreements vary from 2018 to 2025. Expenses associated with operating leases, recorded in operations and maintenance expenses and general and administrative expenses in our statements of operations, were $1.2 million and $1.6 million for the three months ended March 31, 2018 and 2017, respectively. A rental reimbursement included in our lease agreement associated with the office space we leased in June 2015 of $2.0 million , net of amortization, has been recorded as a deferred liability in our condensed consolidated balance sheets as of March 31, 2018. This amount will continue to be amortized against the lease payments over the length of the lease term.

TRANSACTIONS WITH RELATED PARTI

TRANSACTIONS WITH RELATED PARTIES	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
TRANSACTIONS WITH RELATED PARTIES	TRANSACTIONS WITH RELATED PARTIES Affiliated Directors The SXE GP Board is comprised of two directors designated by EIG (one of which must be independent), two directors designated by Tailwater (one of which must be independent), two directors designated by the Lenders (one of which must be independent) and one director by majority. Our non-employee directors are reimbursed for certain expenses incurred for their services to us. The director services fees and expenses are included in general and administrative expenses in our statements of operations. We incurred fees and expenses related to the services from our affiliated directors as follows (in thousands): Three Months Ended March 31, 2018 2017 EIG 36 35 Tailwater 38 36 Total fees and expenses paid for director services to affiliated entities $ 74 $ 71 Southcross Energy Partners GP, LLC (our General Partner) Our General Partner does not receive a management fee or other compensation for its management of us. However, our General Partner and its affiliates are entitled to reimbursements for all expenses incurred on our behalf, including, among other items, compensation expense for all employees required to manage and operate our business. We incurred expenses related to these reimbursements as follows (in thousands): Three Months Ended March 31, 2018 2017 Reimbursements included in general and administrative expenses $ 1,673 $ 4,697 Reimbursements included in operations and maintenance expenses 3,378 3,912 Total reimbursements to our General Partner and its affiliates $ 5,051 $ 8,609 Other Transactions with Affiliates We have a gas gathering and processing agreement (the “G&P Agreement”) and an NGL sales agreement (the “NGL Agreement”) with an affiliate of Holdings. Under the terms of these commercial agreements, we transport, process and sell rich natural gas for the affiliate of Holdings in return for agreed-upon fixed fees, and we can sell natural gas liquids that we own to Holdings at agreed-upon fixed prices. The NGL Agreement also permits us to utilize Holdings’ fractionation services at market-based rates. We had purchases of NGLs from Holdings of $0.1 million and $0.2 million for the three months ended March 31, 2018 and 2017, respectively. We recorded revenues from affiliates of $52.8 million and $40.8 million for the three months ended March 31, 2018 and 2017, respectively, in accordance with the G&P Agreement, the NGL Agreement and the series of commercial agreements. We had accounts receivable due from affiliates of $30.5 million and $33.2 million as of March 31, 2018 and December 31, 2017 , respectively, and accounts payable due to affiliates of $1.0 million and $0.4 million as of March 31, 2018 and December 31, 2017 , respectively. The affiliate receivable and payable balances are related primarily to transactions associated with Holdings, noted above, and our joint venture investments (defined in Note 11). The receivable balance due from Holdings is current as of March 31, 2018 . In connection with the execution of the Fifth Amendment, on December 29, 2016, the Partnership entered into (i) the Investment Agreement with Holdings and Wells Fargo Bank, N.A., (ii) the Backstop Agreement with Holdings, Wells Fargo Bank, N.A. and the Sponsors and (iii) the Equity Cure Contribution Amendment with Holdings. See Notes 1 and 5 for additional details.

PARTNERS' CAPITAL

PARTNERS' CAPITAL	3 Months Ended
	Mar. 31, 2018
Partners' Capital Notes [Abstract]
PARTNERS' CAPITAL	PARTNERS’ CAPITAL Ownership Our units outstanding as of March 31, 2018 are as follows (in units): Partners’ Capital Owned by Parent Public Holdings Class B General Common Common Convertible Subordinated Partner Units outstanding as of December 31, 2017 22,122,113 26,492,074 18,335,181 12,213,713 1,615,573 Vesting of LTIP units, net 22,330 — — — — In-kind distributions and issuances to general partner to maintain 2.0% ownership — — 320,890 — 7,005 Units outstanding as of March 31, 2018 22,144,443 26,492,074 18,656,071 12,213,713 1,622,578 Common Units Our common units represent limited partner interests in us. The holders of our common units are entitled to participate in our distributions (to the extent distributions are made) and are entitled to exercise the rights and privileges available to limited partners under our Partnership Agreement. Class B Convertible Units As of March 31, 2018, the Class B Convertible Units consist of 18,656,071 units, inclusive of any Class B PIK Units issued. The Class B Convertible Units have the same rights, preferences and privileges, and are subject to the same duties and obligations, as our common units, with certain exceptions as noted below. Our Partnership Agreement does not allow additional Class B Convertible Units (other than Class B PIK Units) to be issued without the prior approval of our General Partner and the holders of a majority of the outstanding Class B Convertible Units. As of March 31, 2018 , all of our outstanding Class B Convertible Units were indirectly owned by Holdings. Distribution Rights: The holders of the Class B Convertible Units receive quarterly distributions in an amount equal to $0.3257 per unit paid in Class B PIK Units (based on a unit issuance price of $18.61 ) within 45 days after the end of each quarter. Our General Partner was entitled, and has exercised its right, to retain its 2.0% general partner interest in us in connection with the original issuance of Class B Convertible Units. In connection with future distributions of Class B PIK Units, the General Partner is entitled to a corresponding distribution to maintain its 2.0% general partner interest in us. Conversion Rights: The Class B Convertible Units are convertible into common units on a one-for-one basis and, once converted, will participate in cash distributions pari passu with all other common units. The conversion of Class B Convertible Units will occur on the date we (i) make a quarterly distribution equal to or greater than $0.44 per common unit, (ii) generate Class B Distributable Cash Flow (as defined in our Partnership Agreement) in an amount sufficient to pay the declared distribution on all units for the two quarters immediately preceding the date of conversion (the “measurement period”) and (iii) forecast paying a distribution equal to or greater than $0.44 per unit from forecasted Class B Distributable Cash Flow on all outstanding common units for the two quarters immediately following the measurement period. Voting Rights: The Class B Convertible Units generally have the same voting rights as common units, and have one vote for each common unit into which such units are convertible. Subordinated Units Subordinated units represent limited partner interests in us and convert to common units at the end of the Subordination Period (as defined in our Partnership Agreement). The principal difference between our common units and our subordinated units is that in any quarter during the Subordination Period, holders of the subordinated units are not entitled to receive any distribution of available cash until the common units have received the minimum quarterly distribution plus any arrearages in the payment of the minimum quarterly distribution from prior quarters. Subordinated units do not accrue arrearages. Beginning with the third quarter of 2014, until such time we have a Distributable Cash Flow Ratio of at least 1.0 , Holdings, the indirect holder of the subordinated units, has waived the right to receive distributions on any subordinated units that would cause the Distributable Cash Flow Ratio to be less than 1.0 . In addition, the Fifth Amendment imposed additional restrictions on our ability to declare and pay quarterly cash distributions with respect to our subordinated units. See Note 5. General Partner Interests As defined by our Partnership Agreement, general partner units are not considered to be units (common or subordinated), but are representative of our General Partner’s 2.0% ownership interest in us. Our General Partner has received general partner unit PIK distributions in connection with the Class B Convertible Units. In connection with other equity issuances, our General Partner has made capital contributions in exchange for additional general partner units to maintain its 2.0% ownership interest in us.

INCENTIVE COMPENSATION

INCENTIVE COMPENSATION	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
INCENTIVE COMPENSATION	INCENTIVE COMPENSATION Unit Based Compensation Long-Term Incentive Plan The 2012 Long-Term Incentive Plan (“LTIP”) provides incentive awards to eligible officers, employees and directors of our General Partner. Awards granted to employees under the LTIP generally vest over a three year period in equal annual installments, or in the event of a change in control, in either a common unit or an amount of cash equal to the fair market value of a common unit at the time of vesting, as determined by our management at its discretion. These awards also include distribution equivalent rights that grant the holder the right to receive an amount equal to the cash distributions on common units during the period the award remains outstanding. On November 9, 2015, the holders of a majority of our limited partner interests approved an amendment to the LTIP which increased the number of common units that may be granted as awards by 4,500,000 units. The term of the LTIP also was extended to a period of 10 years following the amendment's adoption. The following table summarizes information regarding awards of units granted under the LTIP: Units Weighted-Average Fair Unvested - December 31, 2017 98,096 $ 10.95 Forfeited units (4,468 ) $ 13.63 Units recaptured for tax withholdings (1) (10,128 ) $ 9.08 Vested units (1) (22,330 ) $ 9.38 Unvested - March 31, 2018 61,170 $ 7.94 (1) The weighted-average fair value price on the date of vesting for our vested units was $1.79 for the three months ended March 31, 2018. The weighted-average fair value price on the date of vesting for our units recaptured for tax withholdings was $1.79 for the three months ended March 31, 2018. For the three months ended March 31, 2018 , we did not grant any equity awards under the LTIP. As of March 31, 2018 , we had total unamortized compensation expense of $0.1 million related to unvested awards. Compensation expense associated with awards is expected to be recognized over the three -year vesting period from each equity award’s grant date. As of March 31, 2018 , we had 5,344,600 units available for issuance under the LTIP. Unit Based Compensation Expense The following table summarizes information regarding recognized compensation expense, which is included in general and administrative and operations and maintenance expenses in our statements of operations (in thousands): Three Months Ended March 31, 2018 2017 Unit-based compensation $ 65 $ 257 Employee Savings Plan We have employee savings plans under Sections 401(a) and 401(k) of the Internal Revenue Code of 1986, as amended, whereby employees of our General Partner may contribute a portion of their base compensation to the employee savings plan, subject to limits. We provide a matching contribution each payroll period equal to 100% of each employee’s contribution up to the lesser of 6% of the employee’s eligible compensation or $16,500 annually for the period. The following table summarizes information regarding contributions and the expense recognized for the matching contributions, which is included in operating and maintenance expense and general and administrative expense in our statements of operations (in thousands): Three Months Ended March 31, 2018 2017 Matching contributions expensed for employee savings plan $ 177 $ 188

REVENUES

REVENUES	3 Months Ended
	Mar. 31, 2018
Revenues [Abstract]
REVENUES	(1) Commodity-sensitive revenues are included in these categories as well. (2) As a result of the FASB issuance of ASC 606, we identified certain natural gas purchase contracts that contained producer fees which were previously recognized as revenue for services provided to producers. The fee revenue which was previously presented within revenue now is presented within the costs of natural gas and liquids sold line item within the condensed consolidated statement of operations beginning on January 1, 2018. Therefore, beginning on January 1, 2018, the producer fee revenue of $12.5 million that were previously recognized as revenue under ASC 605 are recognized as reductions to the costs of natural gas and liquids sold line item within the condensed consolidated statement of operations.

EQUITY IN JOINT VENTURES

EQUITY IN JOINT VENTURES	3 Months Ended
	Mar. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
EQUITY IN JOINT VENTURES	INVESTMENTS IN JOINT VENTURES We own equity interests in three joint ventures with Targa as our joint venture partner. T2 Eagle Ford Gathering Company LLC (“T2 Eagle Ford”), T2 LaSalle Gathering Company LLC (“T2 LaSalle”) and T2 Cogen operate pipelines and a cogeneration facility located in South Texas. We indirectly own a 50% interest in T2 Eagle Ford, a 50% interest in T2 Cogen and a 25% interest in T2 LaSalle. We pay our proportionate share of the joint ventures’ operating costs, excluding depreciation and amortization, through lease capacity payments. As a result, our share of the joint ventures’ losses is related primarily to the joint ventures’ depreciation and amortization. Our maximum exposure to loss related to these joint ventures includes our equity investment, any additional capital contributions and our share of any operating expenses incurred by the joint ventures. The joint ventures’ summarized financial data from their statements of operations for the three months ended March 31, 2018 and 2017 is as follows (in thousands): Three Months Ended March 31, 2018 2017 Revenue T2 Eagle Ford $ 1,062 $ 1,141 T2 Cogen 211 83 T2 LaSalle 385 385 Net loss T2 Eagle Ford $ (4,668 ) $ (4,906 ) T2 Cogen (864 ) (992 ) T2 LaSalle (1,478 ) (1,468 ) Our equity in losses of joint venture investments is comprised of the following for the three months ended March 31, 2018 and 2017 (in thousands): Three Months Ended March 31, 2018 2017 T2 Eagle Ford $ (2,334 ) $ (2,453 ) T2 Cogen (432 ) (496 ) T2 LaSalle (370 ) (367 ) Equity in losses of joint venture investments $ (3,136 ) $ (3,316 ) Our investments in joint ventures is comprised of the following as of March 31, 2018 and December 31, 2017 (in thousands): March 31, 2018 December 31, 2017 T2 Eagle Ford $ 89,999 $ 92,248 T2 Cogen 3,992 4,425 T2 LaSalle 14,711 15,074 Investments in joint ventures $ 108,702 $ 111,747

CONCENTRATION OF CREDIT RISK AN

CONCENTRATION OF CREDIT RISK AND TRADE ACCOUNTS RECEIVABLE	3 Months Ended
	Mar. 31, 2018
Risks and Uncertainties [Abstract]
CONCENTRATION OF CREDIT RISK AND TRADE ACCOUNTS RECEIVABLE	CONCENTRATION OF CREDIT RISK Our primary markets are in South Texas, Alabama and Mississippi. We have a concentration of revenues and trade accounts receivable due from customers engaged in the production, trading, distribution and marketing of natural gas and NGL products. These concentrations of customers may affect overall credit risk in that these customers may be affected similarly by changes in economic, regulatory or other factors. We analyze our customers’ historical financial and operational information before extending credit. Our top ten customers, excluding affiliates, for the three months ended March 31, 2018 and 2017 represent the following percentages of consolidated revenue: Three Months Ended March 31, 2018 2017 Top ten customers 50.2 % 56.0 % We did not have any customers, excluding affiliates, exceed 10% of total consolidated revenue for the three months ended March 31, 2018 and 2017. For the three months ended March 31, 2018 and 2017 , we did not experience significant non-payment for services. We had no allowance for uncollectible accounts receivable at March 31, 2018 .

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	3 Months Ended
	Mar. 31, 2018
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS None.

SUPPLEMENTAL INFORMATION

SUPPLEMENTAL INFORMATION	3 Months Ended
	Mar. 31, 2018
Supplemental Cash Flow Elements [Abstract]
SUPPLEMENTAL INFORMATION	SUPPLEMENTAL INFORMATION Supplemental Cash Flow Information (in thousands) Three Months Ended March 31, 2018 2017 Supplemental Disclosures: Cash paid for interest $ 8,809 $ 8,419 Supplemental disclosures of non-cash investing and financing activities: Accounts payable related to capital expenditures 2,062 3,529 Capital lease obligations 95 138 Class B Convertible unit in-kind distributions 542 404 Capitalization of Interest Cost We capitalize interest on projects during their construction period. Once a project is placed in service, capitalized interest, as a component of the total cost of the construction, is depreciated over the estimated useful life of the asset constructed. We incurred the following interest costs (in thousands): Three Months Ended March 31, 2018 2017 Total interest costs $ 10,095 $ 9,297 Capitalized interest included in property, plant and equipment, net (85 ) (194 ) Interest expense $ 10,010 $ 9,103 Southcross Assets Considered Leases to Third Parties We have pipelines that transport natural gas to two power plants in Nueces County, Texas under fixed-fee contracts. The contracts have a primary term through 2029 and an option to extend the agreements by an additional term of up to ten years. These contracts are considered operating leases under the applicable accounting guidance. Future minimum annual demand payment receipts under these agreements as of March 31, 2018 were as follows: $1.6 million for the remainder of 2018; $2.2 million in 2019; $2.2 million in 2020; $1.5 million in 2021; $1.5 million in 2022 and $10.2 million thereafter. The revenue for the demand payments is recognized on a straight-line basis over the term of the contract. The demand fee revenues under the contracts were each $0.7 million for the three months ended March 31, 2018 and 2017, respectively, and have been included within transportation, gathering and processing fees within Note 10. These amounts do not include variable fees based on the actual gas volumes delivered under the contracts. Variable fees recognized in revenues within transportation, gathering and processing fees within Note 10 were $0.2 million and $0.8 million for the three months ended March 31, 2018 and 2017, respectively. Deferred revenue associated with these agreements was $11.5 million and $11.6 million at March 31, 2018 and December 31, 2017, respectively.

BASIS OF PRESENTATION AND SUM23

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation We prepared this report under the rules and regulations of the SEC and in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial statements. Accordingly, these condensed consolidated financial statements do not include all of the disclosures required by GAAP and should be read in conjunction with our 2017 Annual Report on Form 10-K (“ 2017 Annual Report on Form 10-K”). The condensed consolidated financial statements as of March 31, 2018 and December 31, 2017 , and for the three months ended March 31, 2018 and 2017 , are unaudited and have been prepared on the same basis as the audited financial statements included in our 2017 Annual Report on Form 10-K. However, on January 1, 2018, the Partnership adopted Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606) (“ASC 606”), using the modified retrospective method. Accordingly, our condensed consolidated financial statements for the three months ended March 31, 2018 have been prepared in accordance with the updated accounting principles under the new standard. Adjustments (consisting of normal recurring adjustments) necessary for a fair presentation of the results of operations and financial position have been included herein. All intercompany accounts and transactions have been eliminated in the preparation of the accompanying condensed consolidated financial statements. The accompanying unaudited condensed consolidated financial statements were prepared in conformity with GAAP, which requires management to make various estimates and assumptions that may affect the amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the applicable period. Actual results may differ from those estimates. Information for interim periods may not be indicative of our operating results for the entire year. We evaluate events that occur after the balance sheet date, but before the financial statements are issued, for potential recognition or disclosure. Based on the evaluation, we determined that there were no material subsequent events for recognition or disclosure other than those disclosed in this report.
Recent Accounting Pronouncements	Recent Accounting Pronouncements

NET (LOSS) INCOME PER LIMITED24

NET (LOSS) INCOME PER LIMITED PARTNER UNIT AND DISTRIBUTIONS (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Schedule of Reconciliation of Net Income loss	The following is a reconciliation of net loss attributable to limited partners and the limited partner units used in the basic and diluted earnings per unit calculations for the three months ended March 31, 2018 and 2017 (in thousands, except unit and per unit data): Three Months Ended March 31, 2018 2017 Net loss $ (16,837 ) $ (15,383 ) General partner unit in-kind distribution (11 ) (8 ) Net loss attributable to partners $ (16,848 ) $ (15,391 ) General partner's interest (1) $ (348 ) $ (316 ) Class B Convertible limited partner interest (1) (3,849 ) (3,335 ) Limited partners' interest (1) Common $ (10,112 ) $ (9,380 ) Subordinated (2,539 ) (2,360 ) (1) General Partner's and limited partners’ interests are calculated based on the allocation of net losses for the period, net of the General Partner unit in-kind distributions. The Class B Convertible Unit interest is calculated based on the allocation of only net losses for the period. Three Months Ended March 31, Common Units 2018 2017 Interest in net loss $ (10,112 ) $ (9,380 ) Effect of dilutive units - numerator (1) — — Dilutive interest in net loss $ (10,112 ) $ (9,380 ) Weighted-average units - basic 48,626,521 48,521,512 Effect of dilutive units - denominator (1) — — Weighted-average units - dilutive 48,626,521 48,521,512 Basic and diluted net loss per common unit $ (0.21 ) $ (0.19 ) Three Months Ended March 31, Subordinated Units 2018 2017 Interest in net loss $ (2,539 ) $ (2,360 ) Effect of dilutive units - numerator (1) — — Dilutive interest in net loss $ (2,539 ) $ (2,360 ) Weighted-average units - basic 12,213,713 12,213,713 Effect of dilutive units - denominator (1) — — Weighted-average units - dilutive 12,213,713 12,213,713 Basic and diluted net loss per subordinated unit $ (0.21 ) $ (0.19 ) (1) Because we had a net loss for all periods for common units and the subordinated units, the effect of the dilutive units would be anti-dilutive to the per unit calculation. Therefore, the weighted average units outstanding are the same for basic and dilutive net loss per unit for those periods. The weighted average units that were not included in the computation of diluted per unit amounts were 215,878 and 89,089 unvested awards granted under the LTIP for the three months ended March 31, 2018 and 2017, respectively.
Distributions Made to Limited Partners and General Partner, by Distribution	The following table represents the Class B PIK unit distribution paid on the Class B Convertible Units for the periods ended December 31, 2017 and March 31, 2018 (in thousands, except per unit and in-kind distribution units): Payment Date Attributable to the Quarter Ended Per Unit Distribution In-Kind Class B Convertible Unit In-Kind Class B Convertible Distributions (1) In-Kind Unit to General Partner In-Kind General Partner Distribution Value (1) 2018 May 3, 2018 March 31, 2018 $ 0.3257 $ 326,506 $ 532 $ 6,663 $ 11 2017 February 9, 2018 December 31, 2017 $ 0.3257 320,890 $ 542 6,549 $ 11 November 11, 2017 September 30, 2017 0.3257 315,370 741 6,436 15 August 11, 2017 June 30, 2017 0.3257 309,946 983 6,325 20 May 11, 2017 March 31, 2017 0.3257 304,615 1,060 6,216 22 (1) The fair value was calculated as required, based on the common unit price at the quarter end date for the period attributable to the distribution, multiplied by the number of units distributed.

FINANCIAL INSTRUMENTS (Tables)

FINANCIAL INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2018
Derivatives
Schedule of the fair value of the interest rate swap liabilities	The fair values of our interest rate derivative transactions were as follows (in thousands): Significant Other Observable Inputs (Level 2) Fair Value Measurement as of March 31, 2018 December 31, 2017 Current interest rate derivative assets $ 6 $ 1 Non-current interest rate derivative assets 1 1 Total interest rate derivatives $ 7 $ 2
Summary of amounts recognized in interest expense associated with derivatives that are not designated as hedging instruments	The realized and unrealized amounts recognized in interest expense associated with derivatives were as follows (in thousands): Three Months Ended March 31, 2018 2017 Unrealized loss (gain) on interest rate derivatives $ (5 ) $ 2 Realized gain on interest rate derivatives — (15 )

LONG-LIVED ASSETS (Tables)

LONG-LIVED ASSETS (Tables)	3 Months Ended
	Mar. 31, 2018
Property, Plant and Equipment [Abstract]
Schedule of property, plant and equipment	Property, plant and equipment consisted of the following (in thousands): Estimated Useful Life (yrs) March 31, 2018 December 31, 2017 Pipelines 15-30 $ 571,730 $ 571,730 Gas processing, treating and other plants 15 520,480 520,765 Compressors 5-15 78,997 78,997 Rights of way and easements 15 49,897 49,897 Furniture, fixtures and equipment 5 9,746 9,746 Capital lease vehicles 3-5 2,315 2,114 Total property, plant and equipment 1,233,165 1,233,249 Accumulated depreciation and amortization (352,223 ) (334,528 ) Total 880,942 898,721 Construction in progress 6,759 2,173 Land and other 13,653 13,653 Property, plant and equipment, net $ 901,354 $ 914,547

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Schedule of Long-term Debt	Third A&R Revolving Credit Agreement The Third A&R Revolving Credit Agreement is a five -year $200 million revolving credit facility due August 4, 2019 (the “Credit Facility”). Borrowings under our Credit Facility bear interest at the LIBOR plus an applicable margin or a base rate as defined in the Third A&R Revolving Credit Agreement. Pursuant to the Third A&R Revolving Credit Agreement, among other things: (a) the letters of credit sublimit was set at $75 million ; and (b) if we fail to comply with the Consolidated Total Leverage Ratio, Consolidated Senior Secured Leverage Ratio and the Consolidated Interest Coverage Ratio covenants (each as defined in the Third A&R Revolving Credit Agreement, and collectively the “Financial Covenants”) (each such failure, a “Financial Covenant Default”), we have the right (a limited number of times) to cure such Financial Covenant Default by having the Sponsors purchase equity interests in or make capital contributions to us resulting in, among other things, proceeds that, if added to Consolidated EBITDA (as defined in the Third A&R Revolving Credit Agreement) would result in us satisfying the Financial Covenants. Amendments to Third A&R Revolving Credit Agreement On May 7, 2015, we entered into the first amendment to our Third A&R Revolving Credit Agreement among the Partnership, as the borrower, the lenders and other parties thereto (the “First Amendment”). The First Amendment, among other things: (i) revised the maximum Consolidated Total Leverage Ratio set at 5.00 to 1.0 as of the last day of each fiscal quarter after September 30, 2016, without any step-ups in connection with acquisitions; (ii) increased the applicable margins used in connection with the loans and the commitment fee so that the applicable margin for Eurodollar Loans (as used in the Third A&R Revolving Credit Agreement) ranges from 2.00% to 4.50% , the applicable margin for base rate loans ranges from 1.00% to 3.50% and the applicable rate for commitment fees ranges from 0.375% to 0.500% ; and (iii) allowed us an unlimited number of quarterly equity cures related to our Financial Covenant Default through the fourth quarter of 2016, and no more than two in a twelve month period thereafter for the life of the agreement. Beginning on January 1, 2017, we are limited to no more than four equity cures, with no more than two in a twelve month period. On December 29, 2016, we entered into the Fifth Amendment which, among other things: (i) permitted a full waiver for all defaults or events of default arising out of our failure to comply with the financial covenant to maintain a Consolidated Total Leverage Ratio less than 5.00 to 1.00 for the quarter ended September 30, 2016; (ii) reduced the total aggregate commitments under the Third A&R Revolving Credit Agreement from $200 million to $145 million and reduced the sublimit for letters of credit from $75 million to $50 million . Total aggregate commitments was reduced to $125 million on March 31, 2018, and will be further reduced to $120 million on June 30, 2018 and $115 million on December 31, 2018 and will also be reduced in an amount equal to the net proceeds of any Permitted Note Indebtedness (as defined in the Fifth Amendment) we may incur in the future; (iii) modified the borrowings under the Third A&R Revolving Credit Agreement to bear interest at the LIBOR or a base rate plus an applicable margin that cumulatively increases pursuant to the Fifth Amendment by (a) 125 basis points if our Consolidated Total Leverage Ratio is greater than or equal to 5.00 to 1.00 , plus (b) 100 basis points if our Consolidated Total Leverage Ratio is greater than or equal to 6.00 to 1.00 , plus (c) 100 basis points if our Consolidated Total Leverage Ratio is greater than or equal to 7.00 to 1.00 , plus (d) 100 basis points if our Consolidated Total Leverage Ratio is greater than or equal to 8.00 to 1.00 . At our election, the 100 basis point increase to the applicable margin upon our Consolidated Total Leverage Ratio being greater than or equal to 8.00 to 1.00 may be replaced with a 150 basis point increase that is payable in kind; (iv) suspended the Consolidated Total Leverage Ratio and Consolidated Senior Secured Leverage Ratio financial covenants and reduced the Consolidated Interest Coverage Ratio financial covenant requirement from 2.50 to 1.00 to 1.50 to 1.00 for all periods ending on or prior to the Ratio Compliance Date; (v) requires us to generate Consolidated EBITDA in certain minimum amounts beginning with the quarter ending December 31, 2016 and rolling forward thereafter through the quarter ending December 31, 2018; (vi) requires us to maintain at least $3 million of Liquidity (as defined therein) as of the last business day of each calendar week; (vii) restricts our capital expenditures for growth and maintenance to not exceed certain amounts per fiscal year; and (viii) beginning with the fiscal quarter ending March 31, 2019, our Consolidated Total Leverage Ratio cannot exceed 5.00 to 1.00 and our Consolidated Senior Secured Leverage Ratio cannot exceed 3.50 to 1.00 . Until such time as our Consolidated Total Leverage Ratio is less than 5.00 to 1.00 , we will also be restricted from making cash distributions to our unitholders and from entering into acquisition or merger agreements with third-party businesses involving a purchase price greater than $10 million , unless such acquisition is funded entirely using the proceeds from the issuance of equity. In addition, until such time as our Consolidated Total Leverage Ratio is less than or equal to 5.00 to 1.00 , we will be required to repay any outstanding borrowings under the Credit Facility in an amount equal to 50% of our Excess Cash Flow (as defined in the Fifth Amendment). Our Consolidated Total Leverage Ratio was 8.64 to 1.00 as of March 31, 2018. Term Loan Agreement The Term Loan Agreement is a $450 million senior secured term loan facility maturing on August 4, 2021. Borrowings under our Term Loan Agreement bear interest at LIBOR plus 4.25% or a base rate as defined in the respective credit agreement with a LIBOR floor of 1.00% . The facility will amortize in equal quarterly installments in an aggregate amount equal to 1% of the original principal amount, less any mandatory prepayments (as defined in the Term Loan Agreement), $1.064 million , with the remainder due on the maturity date. Senior Unsecured Note On January 2, 2018, Holdings delivered a Backstop Demand (as defined in the Investment Agreement) for each Sponsor to fund their respective pro rata portions of the Sponsor Shortfall Amount (as defined in the Investment Agreement) of $15.0 million in accordance with the Backstop Agreement. As consideration for the amount contributed directly to us by a Sponsor pursuant to the Backstop Agreement, we issued to the Sponsors senior unsecured notes of the Partnership in an aggregate principal amount of $15.0 million (each, an "Investment Note" and collectively, the “Investment Notes”). The Investment Notes mature on November 5, 2019 and bear interest at a rate of 12.5% per annum. Interest on the Investment Note shall be paid-in-kind (“PIK”) (other than with respect to interest payable (i) on or after the maturity date, (ii) in connection with prepayment, or (iii) upon acceleration of the Investment Note, which shall be payable in cash); provided that all interest shall be payable in cash on or after December 31, 2018. The Investment Notes are the unsecured obligation of the Partnership subordinate in right of payment to any of our secured obligations under the Third A&R Revolving Credit Agreement. The senior unsecured note payable includes $0.3 million of PIK interest as of March 31, 2018. Deferred Financing Costs Deferred financing costs are capitalized and amortized as interest expense under the effective interest method over the term of the related debt. The unamortized balance of deferred financing costs is included in long-term debt in the balance sheets. Changes in deferred financing costs are as follows (in thousands): 2018 2017 Deferred financing costs, January 1 $ 8,295 $ 11,474 Capitalization of deferred financing costs 255 96 Amortization of deferred financing costs (846 ) (869 ) Deferred financing costs, March 31 $ 7,704 $ 10,701

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Schedule of Capital Lease Obligations	he capital lease obligation amounts included in the balance sheets were as follows (in thousands): March 31, 2018 December 31, 2017 Other current liabilities $ 463 $ 410 Other non-current liabilities 578 410 Total $ 1,041 $ 820

TRANSACTIONS WITH RELATED PAR29

TRANSACTIONS WITH RELATED PARTIES (Tables)	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
Schedule of Fees, Expenses and Reimbursements Incurred Through Services with Related Parties	We incurred expenses related to these reimbursements as follows (in thousands): Three Months Ended March 31, 2018 2017 Reimbursements included in general and administrative expenses $ 1,673 $ 4,697 Reimbursements included in operations and maintenance expenses 3,378 3,912 Total reimbursements to our General Partner and its affiliates $ 5,051 $ 8,609 We incurred fees and expenses related to the services from our affiliated directors as follows (in thousands): Three Months Ended March 31, 2018 2017 EIG 36 35 Tailwater 38 36 Total fees and expenses paid for director services to affiliated entities $ 74 $ 71

INCENTIVE COMPENSATION (Tables)

INCENTIVE COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of information regarding awards of units granted under the Incentive Plan	The following table summarizes information regarding awards of units granted under the LTIP:
Summary of information regarding recognized compensation expense, which is included in general and administrative expense on consolidated statements of operations	The following table summarizes information regarding recognized compensation expense, which is included in general and administrative and operations and maintenance expenses in our statements of operations (in thousands): Three Months Ended March 31, 2018 2017 Unit-based compensation $ 65 $ 257
Schedule of employer matching contributions	The following table summarizes information regarding contributions and the expense recognized for the matching contributions, which is included in operating and maintenance expense and general and administrative expense in our statements of operations (in thousands): Three Months Ended March 31, 2018 2017 Matching contributions expensed for employee savings plan $ 177 $ 188

REVENUES (Tables)

REVENUES (Tables)	3 Months Ended
	Mar. 31, 2018
Revenues [Abstract]
Schedule of revenues by category	Three Months Ended March 31, Contract Type 2018 2017 Sales of natural gas (1) Fixed Spread $ 96,697 $ 86,504 Sales of NGLs and condensate (1) Fixed Spread 47,220 41,054 Transportation, gathering and processing Fixed Fee 7,673 8,059 Producer fees (2) Fixed Fee — 15,299 Treating and compression Fixed Fee 3,851 3,910 Other N/A 1,189 332 Total revenues $ 156,630 $ 155,158

EQUITY IN JOINT VENTURES (Table

EQUITY IN JOINT VENTURES (Tables)	3 Months Ended
	Mar. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Schedules of joint ventures	The joint ventures’ summarized financial data from their statements of operations for the three months ended March 31, 2018 and 2017 is as follows (in thousands): Three Months Ended March 31, 2018 2017 Revenue T2 Eagle Ford $ 1,062 $ 1,141 T2 Cogen 211 83 T2 LaSalle 385 385 Net loss T2 Eagle Ford $ (4,668 ) $ (4,906 ) T2 Cogen (864 ) (992 ) T2 LaSalle (1,478 ) (1,468 ) Our equity in losses of joint venture investments is comprised of the following for the three months ended March 31, 2018 and 2017 (in thousands): Three Months Ended March 31, 2018 2017 T2 Eagle Ford $ (2,334 ) $ (2,453 ) T2 Cogen (432 ) (496 ) T2 LaSalle (370 ) (367 ) Equity in losses of joint venture investments $ (3,136 ) $ (3,316 ) Our investments in joint ventures is comprised of the following as of March 31, 2018 and December 31, 2017 (in thousands): March 31, 2018 December 31, 2017 T2 Eagle Ford $ 89,999 $ 92,248 T2 Cogen 3,992 4,425 T2 LaSalle 14,711 15,074 Investments in joint ventures $ 108,702 $ 111,747

CONCENTRATION OF CREDIT RISK 33

CONCENTRATION OF CREDIT RISK AND TRADE ACCOUNTS RECEIVABLE (Tables)	3 Months Ended
	Mar. 31, 2018
Consolidated revenue concentration
Schedule of consolidated revenue attributed to Formosa and Sherwin
Top ten customers
Consolidated revenue concentration
Schedule of consolidated revenue attributed to Formosa and Sherwin	Our top ten customers, excluding affiliates, for the three months ended March 31, 2018 and 2017 represent the following percentages of consolidated revenue: Three Months Ended March 31, 2018 2017 Top ten customers 50.2 % 56.0 %

SUPPLEMENTAL INFORMATION (Table

SUPPLEMENTAL INFORMATION (Tables)	3 Months Ended
	Mar. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	Supplemental Cash Flow Information (in thousands) Three Months Ended March 31, 2018 2017 Supplemental Disclosures: Cash paid for interest $ 8,809 $ 8,419 Supplemental disclosures of non-cash investing and financing activities: Accounts payable related to capital expenditures 2,062 3,529 Capital lease obligations 95 138 Class B Convertible unit in-kind distributions 542 404
Capitalization of Interest Cost	We incurred the following interest costs (in thousands): Three Months Ended March 31, 2018 2017 Total interest costs $ 10,095 $ 9,297 Capitalized interest included in property, plant and equipment, net (85 ) (194 ) Interest expense $ 10,010 $ 9,103
Deferred Financing Costs	We capitalize interest on projects during their construction period. Once a project is placed in service, capitalized interest, as a component of the total cost of the construction, is depreciated over the estimated useful life of the asset constructed. We incurred the following interest costs (in thousands):

ORGANIZATION AND DESCRIPTION 35

ORGANIZATION AND DESCRIPTION OF BUSINESS (Details) shares in Millions	Aug. 04, 2014	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)shares	Dec. 31, 2016USD ($)	Sep. 30, 2017USD ($)shares	Dec. 31, 2016
Business Acquisition [Line Items]
Reduction in total aggregate commitments		$ 120,000,000	$ 125,000,000			$ 145,000,000
Sublimit for letters of credit reduction						50,000,000
Consolidated Interest Coverage Ratio			2.50					2.50
Holdings capital commitment						$ 17,000,000
Holdings common units received for capital commitment						11,486,486,000,000
Investment agreement interest rate						12.50%
Consolidated interest coverage ratio amendment			1.50			1.50
Number of Processing Plant			two
Fractionation Plants			one
Number of Treating Facility			one
Investment agreement capital commitment from Holdings				$ 15,000,000
Common unit exchange ratio					$ 0.16
AMID reimbursement expenditures					500,000
AMID termination fee					$ 2,000,000
Southcross Holdings Intermediary LLC ownership interest in the General Partner					100.00%
Southcross Holdings Intermediary LLC ownership interest in SXE					55.00%
AMID common units value in Merger Agreement					$ 185,697,148
AMID common unit price at date of Merger Agreement					$ 13.69		$ 13.69
Series E convertible preferred units | shares					4.5		4.5
Option to acquire AMID common units | shares					4.5		4.5
Equity interest in AMID GP					15.00%
AMID common units held by Holdings to secure potential indemnification					$ 25,000,000
Reverse termination fee					$ 17,000,000
Number of reportable segments			one
Consolidated Total Leverage Ratio						5	5
Cumulative Catch-up adjustment recorded for AIC payments received by customers			$ 2,700,000
Southcross Holdings Common [Member]
Business Acquisition [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	100.00%
Common Units [Member]
Business Acquisition [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	54.00%
General Partner [Member]
Business Acquisition [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	2.00%		2.00%

ACQUISITION (Details)

ACQUISITION (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Business Acquisition [Line Items]
Total revenues	$ 156,630	$ 155,158
Revenue from Related Parties	52,769	40,771
Business Acquisition, Pro Forma Information [Abstract]
Net loss	(16,837)	(15,383)
Class B Convertible Units [Member]
Business Acquisition, Pro Forma Information [Abstract]
Net loss	(3,849)	(3,335)
General Partner [Member]
Business Acquisition, Pro Forma Information [Abstract]
Net loss	$ (348)	$ (316)

NET (LOSS) INCOME PER LIMITED37

NET (LOSS) INCOME PER LIMITED PARTNER UNIT AND DISTRIBUTIONS (Details)	Aug. 04, 2014	Mar. 31, 2018USD ($)$ / sharesshares	Dec. 31, 2017USD ($)$ / sharesshares	Sep. 30, 2017USD ($)$ / shares	Jun. 30, 2017USD ($)$ / shares	Mar. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016	Sep. 30, 2017USD ($)	Jun. 30, 2016shares	Dec. 31, 2015shares
Earnings Per Limited Partner Unit
distributable cash flow ratio								$ 1
Consolidated Total Leverage Ratio							5	5
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | shares		215,878				89,089
Net loss attributable to partners		$ (16,848,000)				$ (15,391,000)
General partner's interest		(16,837,000)				(15,383,000)
Limited partners' interest		(16,837,000)				(15,383,000)
General Partner [Member]
Earnings Per Limited Partner Unit
Preferred Units Cumulative Right to Receive Future Cash Distributions		$ 6,663,000	$ 6,549,000	$ 6,436,000	$ 6,325,000	6,216,000		$ 6,436,000
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	2.00%	2.00%
Net Income (Loss) Allocated to General Partners		$ (337,000)
General partner unit in-kind distribution		11,000				8,000
General partner's interest		(348,000)				(316,000)
Limited partners' interest						(308,000)
Southcross Holdings Common [Member]
Earnings Per Limited Partner Unit
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	100.00%
Class B Convertible Units [Member]
Earnings Per Limited Partner Unit
Preferred Units Cumulative Right to Receive Future Cash Distributions		326,506,000	$ 320,890,000	$ 315,370,000	$ 309,946,000	304,615,000		$ 315,370,000
General partner's interest		(3,849,000)				(3,335,000)
Limited partners' interest		(3,849,000)				(3,335,000)
Limited Partner, units authorized
Earnings Per Limited Partner Unit
Limited Partner, units outstanding | shares									21,982,325	15,005,588
Limited partners' interest		(10,112,000)				(9,380,000)
Interest in net loss		(10,112,000)				(9,380,000)
Dilutive interest in net loss		$ (10,112,000)				$ (9,380,000)
Weighted-average units - basic | shares		48,626,521				48,521,512
Weighted-average units - dilutive | shares		48,626,521				48,521,512
Basic and diluted net loss per common unit | $ / shares		$ (0.21)				$ (0.19)
Subordinated Units [Member]
Earnings Per Limited Partner Unit
Limited Partner, units outstanding | shares		12,213,713	12,213,713						12,213,713	12,213,713
Limited partners' interest		$ (2,539,000)				$ (2,360,000)
Interest in net loss		(2,539,000)				(2,360,000)
Dilutive interest in net loss		$ (2,539,000)				$ (2,360,000)
Weighted-average units - basic | shares		12,213,713				12,213,713
Weighted-average units - dilutive | shares		12,213,713				12,213,713
Basic and diluted net loss per common unit | $ / shares		$ (0.21)				$ (0.19)
Class B Convertible Units [Member]
Earnings Per Limited Partner Unit
Distribution Made to Member or Limited Partner Minimum Quarterly Distributions Declared Per Unit | $ / shares		$ 0.3257
Class B Convertible Units [Member] | Class B Convertible Units [Member]
Earnings Per Limited Partner Unit
Limited Partner, units outstanding | shares		18,656,071
Common Units [Member] | Limited Partner, units authorized
Earnings Per Limited Partner Unit
Limited partners' interest						$ (9,380,000)
Cash Distribution [Member]
Earnings Per Limited Partner Unit
Distribution Made to Member or Limited Partner Unit Distributions Per Unit | $ / shares		$ 0.3257	$ 0.3257	$ 0.3257	$ 0.3257	$ 0.3257
Maximum [Member] | Cash Distribution [Member]
Earnings Per Limited Partner Unit
Distribution Made to Member or Limited Partner Distribution Period		45 days

NET (LOSS) INCOME PER LIMITED38

NET (LOSS) INCOME PER LIMITED PARTNER UNIT AND DISTRIBUTIONS (Distributions) (Details) - USD ($)	Aug. 04, 2014	May 15, 2013	Apr. 12, 2013	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2017
Common Units [Member]
Distributions made to Limited Partner [Line Items]
Ownership interest held by general partners (as a percent)	54.00%
Class B Convertible Units [Member]
Series A preferred units , PIK distribution earned
In-Kind Unit Distribution (in dollars)				$ 532,000	$ 542,304,000	$ 741,120,000	$ 982,529,000	$ 1,060,000
Common units, distribution declared and paid
Preferred Units Cumulative Right to Receive Future Cash Distributions				$ 326,506,000	320,890,000	315,370,000	309,946,000	304,615,000	$ 320,890,000
General Partner [Member]
Distributions made to Limited Partner [Line Items]
Ownership interest held by general partners (as a percent)	2.00%			2.00%
Series A preferred units , PIK distribution earned
In-Kind Unit Distribution (in dollars)				$ 0	11,000,000	15,000,000	0	0
In-Kind Distributions (in dollars per unit)				(11,000)				(8,000)
Common units, distribution declared and paid
Preferred Units Cumulative Right to Receive Future Cash Distributions				$ 6,663,000	$ 6,549,000	$ 6,436,000	$ 6,325,000	$ 6,216,000	$ 6,549,000
Class B Convertible Units [Member]
Series A preferred units , PIK distribution earned
Distribution Made to Member or Limited Partner Minimum Quarterly Distributions Declared Per Unit				$ 0.3257
Share Price				$ 18.61
Class B Convertible Units [Member] | Class B Convertible Units [Member]
Distributions made to Limited Partner [Line Items]
Limited Partner, units outstanding				18,656,071
Conversion of Stock, Shares Issued	18,019,811								17,105,875
Series A Convertible Preferred Units [Member]
Distributions made to Limited Partner [Line Items]
Preferred units issued
Cash
Series A preferred units , PIK distribution earned
Distribution Made to Member or Limited Partner Unit Distributions Per Unit				$ 0.3257	$ 0.3257	$ 0.3257	$ 0.3257	$ 0.3257
Maximum [Member] | Cash
Distributions made to Limited Partner [Line Items]
Distribution Made to Member or Limited Partner Distribution Period				45 days

FINANCIAL INSTRUMENTS (Details)

FINANCIAL INSTRUMENTS (Details)	3 Months Ended		6 Months Ended
	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	Jun. 30, 2016MMBTU	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)
Fair value of financial instruments
Fair value of Term Loan Credit Agreement	$ 426,900,000
Derivative Asset				$ 1,000	$ 6,000
Interest Rate Cap, 3.00%, $50M	0
Unrealized Gain (Loss) on Derivatives	5,000	$ 17,000
Derivative, Fair Value, Net	7
Derivative Assets (Liabilities), at Fair Value, Net				$ (2,000)	$ (7,000)
Fair Value of Senior Unsecured Note Payable	15,200,000
Commodity Swaps [Member]
Fair value of financial instruments
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU			0
Interest rate swap liabilities
Fair value of financial instruments
Gain (Loss) on Sale of Derivatives	(5,000)	2,000
Unrealized Gain (Loss) on Derivatives	0	$ (15,000)
Interest Rate Cap 3.00% [Member]
Fair value of financial instruments
Derivative, Notional Amount	$ 50,000,000
Derivative, Cap Interest Rate	3.00%
Derivative, Notional Amount, $40M, January 1, 2018 Maturity	$ 40,000,000
Derivative, Notional Amount, $40M, July1, 2019 Maturity	60,000,000
Interest Rate Cap $50M, 3% [Member] [Member]
Fair value of financial instruments
Derivative, Notional Amount	$ 40,000,000
Derivative, Cap Interest Rate	3.00%
Derivative Liability, Fair Value, Gross Asset	$ 0
Interest Rate Cap $40M, 3% [Member] [Member] [Domain]
Fair value of financial instruments
Derivative, Notional Amount	85,000,000
Fair Value, Measurements, Recurring [Member] | Interest Rate Cap 3.00% [Member]
Fair value of financial instruments
Interest Rate Cap, 3.00%, $40M, July 1, 2019 Maturity	0
Interest Rate Cap 3.00%, $40M, July 1, 2018 Maturity Date	0
Interest Rate Cap 3.00%, $40M, January 1, 2018 Maturity	0
Derivative Liability, Fair Value, Gross Asset	$ 0

FINANCIAL INSTRUMENTS (Details

FINANCIAL INSTRUMENTS (Details 2)	3 Months Ended		6 Months Ended
	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	Jun. 30, 2016MMBTU	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)
Derivatives
Derivative Asset				$ 1,000	$ 6,000
Derivative Asset, Noncurrent				1,000	1,000
Unrealized loss	$ 5,000	$ 17,000
Derivative, Fair Value, Net	7
Derivative Assets (Liabilities), at Fair Value, Net				$ 2,000	$ 7,000
Interest Rate Swap [Member]
Derivatives
Unrealized loss	0	(15,000)
Realized (loss) on derivatives	(5,000)	$ 2,000
Commodity Swaps
Derivatives
Volume of month-ahead swap contracts (in MMBtu) | MMBTU			0
Interest Rate Cap 3.00% [Member]
Derivatives
Notional amount	$ 50,000,000
Derivative, Cap Interest Rate	3.00%
Interest Rate Cap $50M, 3% [Member] [Member]
Derivatives
Notional amount	$ 40,000,000
Derivative Liability, Fair Value, Gross Asset	$ 0
Derivative, Cap Interest Rate	3.00%
Fair Value, Measurements, Recurring [Member] | Interest Rate Cap 3.00% [Member]
Derivatives
Derivative Liability, Fair Value, Gross Asset	$ 0

LONG-LIVED ASSETS (Details)

LONG-LIVED ASSETS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Property, plant and equipment
Gregory Fire Insurance Deductible		$ 500
Gain on insurance proceeds	$ 0	1,500
Intangible Assets, Net (Excluding Goodwill)	1,300
Total property, plant and equipment	1,233,165		$ 1,233,249
Accumulated depreciation and amortization	(352,223)		(334,528)
Property, plant and equipment, net	901,354		914,547
Gain (Loss) on Sale of Assets and Asset Impairment Charges	0	62
Depreciation expense	17,856	17,850
Net proceeds from sales of assets	$ 0	143
Finite-Lived Intangible Asset, Useful Life	30 years
Amortization of Intangible Assets	five
Prepayment on Term Loan made with Gregory Insurance Proceeds		1,000
Construction in progress
Property, plant and equipment
Property, plant and equipment, net	$ 6,759		2,173
Pipelines
Property, plant and equipment
Estimated useful life	30 years
Total property, plant and equipment	$ 571,730		571,730
Gas processing, treating and other plants
Property, plant and equipment
Estimated useful life	15 years
Total property, plant and equipment	$ 520,480		520,765
Compressors
Property, plant and equipment
Estimated useful life	15 years
Total property, plant and equipment	$ 78,997		78,997
Rights of way and easements
Property, plant and equipment
Estimated useful life	15 years
Total property, plant and equipment	$ 49,897		49,897
Furniture, fixtures and equipment
Property, plant and equipment
Estimated useful life	5 years
Total property, plant and equipment	$ 9,746		9,746
Capital lease vehicles
Property, plant and equipment
Total property, plant and equipment	$ 2,315		2,114
Capital lease vehicles | Maximum [Member]
Property, plant and equipment
Estimated useful life	3 years
Capital lease vehicles | Minimum [Member]
Property, plant and equipment
Estimated useful life	5 years
Property, plant and equipment excluding construction in progress and land and other
Property, plant and equipment
Property, plant and equipment, net	$ 880,942		898,721
Land and other
Property, plant and equipment
Property, plant and equipment, net	$ 13,653		$ 13,653
Insurance Settlement [Member]
Property, plant and equipment
Increase (Decrease) in Insurance Settlements Receivable		$ 2,000

LONG-TERM DEBT (Details)

LONG-TERM DEBT (Details)	Aug. 04, 2014USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Jun. 30, 2016USD ($)$ / shares	Sep. 30, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2015USD ($)
LONG TERM DEBT
NGL purchases from Holdings			$ 100,000	$ 200,000
Consolidated Interest Coverage Ratio			2.50					2.50
Consolidated interest coverage ratio amendment			1.50		1.50
Consolidated Total Leverage Ratio, is greater than or equal to 5.00 to 1.00								$ 5
Consolidated Total Leverage Ratio, is greater than or equal to 6.00 to 1.00								6
Minimum liquidity requirement					$ 3,000,000
Consolidated Total Leverage Ratio					5		5
Reduction in total aggregate commitments, June 30, 2018			$ 120,000,000
Reduction in total aggregate commitments, December 31, 2018			115,000,000
Consolidated Total Leverage Ratio, is greater than or equal to 7.00 to 1.00								7
Amortization of deferred financing costs and PIK interest				(869,000)
Long-term Debt			529,752,000						$ 526,817,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net			(1,053,000)						(1,134,000)
Long-term Debt, Current Maturities			4,256,000						4,256,000
Debt Issuance Costs, Net			(7,704,000)	(10,701,000)	$ (11,474,000)			$ (11,474,000)	(8,295,000)
Deferred Financing Costs, Capitalized During Period			255,000	96,000
Amortization of Debt Issuance Costs and Discounts			(846,000)
Long-term Debt, Excluding Current Maturities			$ 517,792,000						514,266,000
Unsecured Debt, Current
Sublimit for letters of credit reduction					50,000,000
Debt Instrument Leverage Ratio			8.6					5
Consolidated Senior Secured Leverage Ratio								3.50
Cash distribution restriction								$ 10,000,000
Excess cash flow								50.00%
Line of Credit Facility, Amount Outstanding			$ 200,000,000		200,000,000			$ 200,000,000
Reduction in total aggregate commitments		$ 120,000,000	125,000,000		$ 145,000,000
Average outstanding borrowings			$ 531,328,000	$ 553,699,000
Line of Credit Facility, Interest Rate Description	0.01
Weighted average interest rate			6.60%	5.80%
Maximum quarterly distributions until the target leverage ratio is achieved (in dollars per share) | $ / shares						$ 0.40
Maximum borrowings			$ 532,952,000	$ 553,805,000
Proceeds from Issuance of Other Long-term Debt	$ 450,000,000
Amortization of Debt Discount (Premium)	0.01
Debt Instrument, Periodic Payment	$ 1,064,000
Debt Instrument, Unamortized Discount						$ (1,600,000)				$ (1,800,000)
Consolidated Total Leverage Ratio, is greater than or equal to 8.00 to 1.00								8
Consolidated Total Leverage Ratio, is greater than or equal to 8.00 to 1.00, that is payable in kind								$ 8
Proceeds from issuance of Senior Unsecured Note			15,000,000
Paid-in-Kind Interest			300,000
General Partner [Member]
LONG TERM DEBT
Line of Credit Facility, Amount Outstanding			25,061,000						24,911,000
Credit Facility, due November 2017
LONG TERM DEBT
Long-term Debt			$ 83,124,000						94,555,000
Debt Instrument Leverage Ratio			5
Line of Credit Facility, Remaining Borrowing Capacity			$ 16,815,000						15,534,000
Applicable margin under LIBOR borrowings	4.25%
Third A&R revolving credit agreement [Member]
LONG TERM DEBT
Debt Instrument, Term			5 years
Term Loan [Member]
LONG TERM DEBT
Long-term Debt			$ 432,332,000						$ 433,396,000
Letters of credit
LONG TERM DEBT
unused borrowings	$ 75,000,000
Credit Agreement, due June 2014
LONG TERM DEBT
Applicable margin under LIBOR borrowings						3.25%
Eurodollar [Member] | Minimum [Member]
LONG TERM DEBT
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum (Deprecated 2016-01-31)			2.00%
Eurodollar [Member] | Maximum [Member]
LONG TERM DEBT
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum (Deprecated 2016-01-31)			4.50%
Base Rate [Member] | Minimum [Member]
LONG TERM DEBT
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum (Deprecated 2016-01-31)			1.00%
Base Rate [Member] | Maximum [Member]
LONG TERM DEBT
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum (Deprecated 2016-01-31)			3.50%
Minimum Commitment Fee [Member]
LONG TERM DEBT
Line of Credit Facility, Commitment Fee Percentage			0.375%
Maximum Commitment Fee [Member]
LONG TERM DEBT
Line of Credit Facility, Commitment Fee Percentage			0.50%

COMMITMENTS AND CONTINGENCIES43

COMMITMENTS AND CONTINGENCIES (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Purchase commitments
Woodsboro Litigation Accrual	$ 7,700,000
Capital Lease Obligations, Current	463,000		$ 410
Capital leases
Amortization expense related to the capital leases	100,000
Capital Lease Obligations Incurred	300,000	$ 400,000
Operating Leases
Expenses associated with operating leases	1,200,000	$ 1,600,000
Deferred Rent Credit	2,000,000
Capital Lease Obligations, Noncurrent	578,000		410
Capital Lease Obligations	$ 1,041,000		$ 820

TRANSACTIONS WITH RELATED PAR44

TRANSACTIONS WITH RELATED PARTIES (Details)	Mar. 08, 2014	Mar. 31, 2018USD ($)director	Mar. 31, 2017USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Dec. 31, 2017USD ($)
Related Party Transactions
Management fees incurred		$ 74,000	$ 71,000
Number of directors | director		1
Related Party Transaction, Amounts of Transaction		$ 5,051,000	8,609,000
Revenue from Related Parties		52,769,000	40,771,000
Due to Affiliate, Current		959,000				$ 378,000
Contractual Agreement, Term	10 years
Due from Affiliate, Current		30,507,000				$ 33,163,000
Management fees incurred | Vested units
Related Party Transactions
Management fees incurred				$ 0	$ 0
EIG [Member]
Related Party Transactions
Management fees incurred		36,000	35,000
Tailwater [Member]
Related Party Transactions
Management fees incurred		$ 38,000	36,000
Director [Member]
Related Party Transactions
board member from an affiliated entity | director		2
valley wells [Member]
Related Party Transactions
Affiliate Costs			2,190,000
General and Administrative Expense [Member]
Related Party Transactions
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party		$ 1,673,000	4,697,000
Operating Expense [Member]
Related Party Transactions
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party		$ 3,378,000	$ 3,912,000

SERIES A PREFERRED UNITS (Detai

SERIES A PREFERRED UNITS (Details) - shares	Aug. 04, 2014	May 15, 2013	Apr. 12, 2013	Mar. 31, 2018
General Partner [Member]
Ownership interest held by general partners (as a percent)	2.00%			2.00%
Preferred units issued
Preferred units issued

PARTNERS' CAPITAL (Details)

PARTNERS' CAPITAL (Details)	Aug. 04, 2014shares	Mar. 31, 2018USD ($)$ / sharesshares	Jun. 30, 2016$ / sharesshares	Dec. 31, 2017USD ($)shares	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2015shares
Preferred Units Conversion Trailing Period		2
Preferred Stock, Participation Rights		1
Maximum quarterly distributions until the target leverage ratio is achieved (in dollars per share) | $ / shares			$ 0.40
Limited Partner, units authorized
Distribution Made to Limited Partner, Unit Distribution		0
Limited Partner, units issued		48,538,451		48,502,090
Limited Partner, units authorized		49,672,885		29,544,524
Limited Partner, units outstanding			21,982,325					15,005,588
Common Stock, Shares, Outstanding		22,144,443		22,122,113
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number		22,330
Southcross Holdings Common [Member]
Distribution Made to Limited Partner, Unit Distribution		0
Ownership interest held by general partners (as a percent)	100.00%
Common Stock, Shares, Outstanding		26,492,074		26,492,074
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number		0
Class B Convertible Units [Member]
Distribution Made to Limited Partner, Unit Distribution		320,890
Preferred Units Cumulative Right to Receive Future Cash Distributions | $		$ 326,506,000		$ 320,890,000	$ 315,370,000	$ 309,946,000	$ 304,615,000
Preferred Units, Outstanding		18,656,071		18,335,181
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number		0
Subordinated Units [Member]
Distribution Made to Limited Partner, Unit Distribution		0
Preferred Units, Outstanding		12,213,713		12,213,713
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number		0
Subordinated Units [Member]
Limited Partner, units issued								12,213,713
Limited Partner, units authorized				12,213,713
Limited Partner, units outstanding		12,213,713	12,213,713	12,213,713				12,213,713
General Partner [Member]
Distribution Made to Limited Partner, Unit Distribution		7,005
Ownership interest held by general partners (as a percent)	2.00%	2.00%
Preferred Units Cumulative Right to Receive Future Cash Distributions | $		$ 6,663,000		$ 6,549,000	$ 6,436,000	$ 6,325,000	$ 6,216,000
Partners' Capital Account, Units		1,622,578		1,615,573
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number		0
Common Units [Member]
Ownership interest held by general partners (as a percent)	54.00%
Class B Convertible Units [Member]
Distribution Made to Member or Limited Partner, Distribution Paid in Cash | $ / shares		$ 0.3257
Conversion criteria-distribution per unit | $ / shares		0.44
Share Price | $ / shares		$ 18.61
Class B Convertible Units [Member] | Class B Convertible Units [Member]
Conversion of Stock, Shares Issued	18,019,811			17,105,875
Limited Partner, units outstanding		18,656,071
TexStar Rich Gas System [Member]
Ownership interest held by general partners (as a percent)	41.00%
Maximum [Member] | Cash Distribution [Member]
Distribution Made to Member or Limited Partner Distribution Period		45 days

INCENTIVE COMPENSATION (Details

INCENTIVE COMPENSATION (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2015
Unit based compensation
Shared-based Compensation Arrangement by Share-based Payment Award, Equity Instruments, Vested, Weighted-Average Fair Value Vesting Date	$ 1.79	$ 2.66
Allocated Share-based Compensation Expense	$ 65,000	$ 257,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Period Increase (Decrease)	(4,468)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 13.63
Shares Paid for Tax Withholding for Share Based Compensation	(10,128)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Recaptured for Tax Withholding, Weighted Average Grant Date Fair Value	$ 9.08
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	(22,330)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 9.38
Shared-based Compensation Arrangement by Share-based Payment Award, Equity Instruments, Recaptured for Tax Withholding, Vested, Weighted-Average Fair Value Vesting Date	$ 1.79	$ 2.64
Employee Savings Plan [Member]
Unit based compensation
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 177,000	$ 188,000
Employer matching contribution, percent of employee's contribution	100.00%
Weighted-average grant date fair value
Employer matching contribution, percent of employees' gross pay	6.00%
Maximum annual contributions by employer, amount (per employee)	$ 16,500
Long Term Incentive Plan [Member]
Unit based compensation
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	61,170		98,096
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 7.94		$ 10.95
Weighted-average grant date fair value
Long Term Incentive Phantom Units approved				4,500,000
Incentive Plan
Unit based compensation
Vesting period	3 years
Weighted-average grant date fair value
Share-based compensation cost not yet recognized	$ 100,000
Units available for issuance (in shares)	5,344,600
3yr vesting period [Domain] | Incentive Plan
Weighted-average grant date fair value
Period of amortization of compensation expense	3 years

REVENUES (Details)

REVENUES (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues [Abstract]
Producer Fee Revenue, ASC 606 Adjustment	$ 13,000
Sales of natural gas	96,697	$ 86,504
Sales of NGLs and condensate	47,220	41,054
Transportation, gathering and processing fees	7,673	8,059
Producer fee revenue	0	15,299
Treating fee revenue	3,851	3,910
Other (1)	1,189	332
Total revenues (Note 10)	$ 156,630	$ 155,158

EQUITY IN JOINT VENTURES (Detai

EQUITY IN JOINT VENTURES (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)joint_venture	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)	Aug. 04, 2014
Income (Loss) from Equity Method Investments	$ (3,136)	$ (3,316)
number of joint ventures | joint_venture	3
Equity Method Investment Summarized Financial Information, Equity	$ 108,702		$ 111,747
Natural Gas Midstream Revenue	156,630	155,158
Net Income (Loss) Attributable to Parent	(16,837)	(15,383)
Revenues	103,861	114,387
T2 Eagle Ford [Member]
Income (Loss) from Equity Method Investments	(2,334)	(2,453)
Equity Method Investment Summarized Financial Information, Equity	89,999		92,248
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	(4,668)	(4,906)
Natural Gas Midstream Revenue	1,062	1,141
T2 Cogen [Member]
Income (Loss) from Equity Method Investments	(432)	(496)
Equity Method Investment Summarized Financial Information, Equity	3,992		4,425
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	(864)	(992)
Natural Gas Midstream Revenue	211	83
T2 LaSalle [Member]
Income (Loss) from Equity Method Investments	(370)	(367)
Equity Method Investment Summarized Financial Information, Equity	14,711		$ 15,074
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	(1,478)	(1,468)
Natural Gas Midstream Revenue	$ 385	$ 385
T2 LaSalle [Member]
Equity Method Investment, Ownership Percentage				25.00%
T2 Cogen [Member]
Equity Method Investment, Ownership Percentage				50.00%
T2 Eagle Ford [Member]
Equity Method Investment, Ownership Percentage	50.00%

CONCENTRATION OF CREDIT RISK 50

CONCENTRATION OF CREDIT RISK AND TRADE ACCOUNTS RECEIVABLE (Details) - Top ten customers - Customer concentration - Consolidated revenue - customer	3 Months Ended		6 Months Ended	9 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jun. 30, 2015	Sep. 30, 2017
Consolidated revenue concentration
Number of top customers			10	10
Concentration risk percentage	50.20%	56.00%

SUBSEQUENT EVENTS (Details) (De

SUBSEQUENT EVENTS (Details) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)
Capital Contribution to T2 Cogen [Line Items]
Return of Capital Contributions to T2 Cogen	$ 26

SUPPLEMENTAL INFORMATION (Detai

SUPPLEMENTAL INFORMATION (Details) $ in Thousands	Mar. 08, 2014	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Operating Leased Assets [Line Items]
Interest Paid, Net		$ 8,809	$ 8,419
Proceeds from Income Tax Refunds		0	0
Capital Expenditures Incurred but Not yet Paid		2,062	3,529
Repayments of Debt and Capital Lease Obligations		95	138
Noncash Financing Activities, Accrued Distribution on Long Term Incentive Plan		0	0
Interest Costs Incurred [Abstract]
Total interest costs		10,095	9,297
Capitalized interest included in property, plant and equipment, net		(85)	(194)
Interest expense		10,010	9,103
Deferred Financing Costs [Roll Forward]
Deferred financing costs, January 1		7,704	10,701	$ 7,704	$ 8,295	$ 11,474
Deferred Financing Costs, Capitalized During Period		255	96
Amortization of Debt Issuance Costs and Discounts		846
Amortization of deferred financing costs			(869)
Deferred financing costs, September 30		7,704	10,701
Number of power plants				2
Contractual agreement, term	10 years
Contingent fees		(700)
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability		(200)	(800)
Deferred Revenue				$ 11,500	$ 11,600
Paid-in-Kind Interest		300
Natural Gas Pipeline Contracts [Member]
Deferred Financing Costs [Roll Forward]
Operating Leases, Future Minimum Payments, Due in Two Years				1,600
Operating leases, future minimum payments due in third year				2,200
Operating Leases, Future Minimum Payments, Due in Four Years				2,200
Operating leases, future minimum payments due in sixth year				1,500
Operating leases, future minimum payments due after sixth year				1,500
Operating Leases, Future Minimum Payments, Due Thereafter				$ 10,200
valley wells [Member]
Deferred Financing Costs [Roll Forward]
Affiliate Costs			2,190
Class B Convertible Units [Member]
Deferred Financing Costs [Roll Forward]
Temporary Equity Accretion Preferred Unit In-kind Distribution			(404)
Class B Convertible Units [Member] | Class B Convertible Units [Member]
Deferred Financing Costs [Roll Forward]
Temporary Equity Accretion Preferred Unit In-kind Distribution		(542)	(404)
Limited Partner, units authorized | Class B Convertible Units [Member]
Deferred Financing Costs [Roll Forward]
Temporary Equity Accretion Preferred Unit In-kind Distribution		$ 422	$ 315