Southcross Energy Partners 10-Q 14 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Nov. 09, 2018
Entity Registrant Name	Southcross Energy Partners, L.P.
Entity Central Index Key	1,547,638
Document Type	10-Q
Document Period End Date	Sep. 30, 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	Q3
Common Units [Member]
Entity Common Stock, Shares Outstanding		48,670,936
Subordinated Units [Member]
Entity Common Stock, Shares Outstanding		12,213,713
Class B Convertible Units [Member]
Entity Common Stock, Shares Outstanding		19,314,797

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 3,048	$ 5,218
Trade accounts receivable	23,193	33,920
Due from Affiliate, Current	48,450	33,163
Prepaid expenses	1,662	2,592
Other current assets	8,113	497
Total current assets	84,466	75,390
Property, plant and equipment, net	869,547	914,547
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	102,652	111,747
Other assets	2,393	2,519
Total assets	1,059,058	1,104,203
Current liabilities:
Accounts payable and accrued liabilities	51,086	57,782
Due to Affiliate, Current	36	378
Other Long-term Debt, Current	522,787	4,256
Other current liabilities	13,457	12,976
Total current liabilities	587,366	75,392
Long-term Debt, Excluding Current Maturities	0	514,266
Other non-current liabilities	17,300	14,979
Total liabilities	604,666	604,637
Partners' capital:
Total partners' capital	454,392	499,566
Liabilities, preferred units, and partners' capital:
Total liabilities, preferred units and partners' capital	1,059,058	1,104,203
Limited Partner, units authorized
Partners' capital:
Total partners' capital	184,839	215,146
Class B Convertible Units [Member]
Partners' capital:
Total partners' capital	260,512	266,725
Subordinated Units [Member]
Partners' capital:
Total partners' capital	643	8,302
General Partner interest [Member]
Partners' capital:
General Partner interest	8,398	9,393
Total partners' capital	$ 8,398	$ 9,393

CONDENSED CONSOLIDATED BALANC_2

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	48,636,517
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:
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		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues	$ 79,387	$ 122,099	$ 261,591	$ 364,456
Revenue from Related Parties	75,417	48,379	187,263	129,458
Total revenues (Note 10)	154,804	170,478	448,854	493,914
Expenses:
Cost of natural gas and liquids sold	118,377	136,723	346,305	388,362
Operations and maintenance	13,626	14,278	41,975	43,779
Depreciation and amortization	17,787	17,521	53,549	53,673
General and administrative	5,613	6,557	15,529	19,616
Asset Impairment Charges	0	1,120	0	1,769
Loss (gain) on sale of assets, net	(84)	186	(637)	(5)
Total expenses	155,319	176,385	456,721	507,194
Loss from operations	(515)	(5,907)	(7,867)	(13,280)
Income (Loss) from Equity Method Investments	(3,161)	(3,218)	(9,449)	(9,865)
Interest expense	(11,158)	(9,931)	(32,263)	(28,670)
Other Cost and Expense, Operating	(14,319)	(13,149)	(41,712)	(37,027)
Loss before income tax expense	(14,834)	(19,056)	(49,579)	(50,307)
Income tax expense	0	(2)	0	(4)
Net loss	(14,834)	(19,058)	(49,579)	(50,311)
General partner unit in-kind distribution				50
Net loss attributable to partners	(14,845)	(19,078)	(49,612)	(50,361)
Earnings per unit and distributions declared
Net loss allocated to limited partner, basic and diluted			(49,579)	(50,311)
Gain on insurance proceeds	0	0	0	1,500
General Partner [Member]
Expenses:
Net loss	(308)	(396)	(1,024)
General partner unit in-kind distribution	11	20	33	50
Earnings per unit and distributions declared
Net loss allocated to limited partner, basic and diluted				(1,006)
Common Limited Partners [Member]
Earnings per unit and distributions declared
Net loss allocated to limited partner, basic and diluted	$ (8,833)	$ (11,545)	$ (29,659)	$ (30,590)
Weighted average number of limited partner units outstanding, basic and diluted	48,658	48,574	48,640	48,545
Basic and diluted loss per unit (in dollars per unit)	$ (0.18)	$ (0.24)	$ (0.61)	$ (0.63)
Subordinated Limited Partners [Member]
Earnings per unit and distributions declared
Net loss allocated to limited partner, basic and diluted	$ (2,217)	$ (2,902)	$ (7,446)	$ (7,694)
Weighted average number of limited partner units outstanding, basic and diluted	12,214	12,214	12,214	12,214
Basic and diluted loss per unit (in dollars per unit)	$ (0.18)	$ (0.24)	$ (0.61)	$ 0

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (14,834)	$ (19,058)	$ (49,579)	$ (50,311)

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Proceeds from Issuance of Unsecured Debt	$ 15,000	$ 0
Cash flows from operating activities:
Net loss	(49,579)	(50,311)
Depreciation and amortization	53,549	53,673
Unit-based compensation	210	1,241
Other Noncash Expense	4,143	2,719
Gain (Loss) on Sale of Assets and Asset Impairment Charges	(637)	(5)
Unrealized gain on financial instruments	(13)	(15)
Income (Loss) from Equity Method Investments, Net of Dividends or Distributions	9,449	9,865
Asset Impairment Charges	0	1,769
Gain on insurance proceeds	0	(1,500)
Other Operating Activities, Cash Flow Statement	(189)	(411)
Changes in operating assets and liabilities:	(4,559)	12,503
Increase (Decrease) in Prepaid Expense and Other Assets	(7,172)	28
Increase (Decrease) in Other Noncurrent Assets	636	(22)
Increase (Decrease) in Accounts Payable and Accrued Liabilities	(7,687)	(1,912)
Increase (Decrease) in Other Operating Liabilities	5,188	(1,778)
Net Cash Provided by (Used in) Operating Activities	3,339	25,836
Net cash provided by operating activities
Capital expenditures	(9,694)	(17,027)
Proceeds from Contribution in Aid of Construction	(7)	(8,876)
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	693	2,974
Investment contributions to joint venture investments	(354)	(412)
Net cash used in investing activities	(9,362)	(3,589)
Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]
Repayments of Long-term Lines of Credit	(11,431)	(24,000)
Repayments of Long-term Debt	(3,192)	(4,289)
Borrowings under our credit facility	(461)	(369)
Financing costs	(256)	(44)
Payments Related to Tax Withholding for Share-based Compensation	(8)	(119)
Proceeds from Contributions from Parent	4,201	0
Net Cash Provided by (Used in) Financing Activities	3,853	(28,821)
Net decrease in cash and cash equivalents	(2,170)	(6,574)
Cash and cash equivalents — Beginning of period	5,218	21,226
Cash and cash equivalents — End of period	$ 3,048	$ 14,652

CONDENSED CONSOLIDATED STATEM_4

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	(50,311)
Payments of Stock Issuance Costs				11,058					1,019
Net loss allocated to limited partner, basic and diluted	(50,311)	(30,590)		(11,058)		(7,694)		$ (7,687)	(1,006)		$ (30,560)
Series A convertible preferred unit in-kind distribution and fair value adjustment			$ 1,905	(2,447)	$ (2,447)		$ 479			$ 63
Class B Convertible unit in-kind distribution		31		11		8			(50)
Equity contribution from Holdings	5	0				0			5
Retention bonus funded by Holdings		2,281
Partners' Capital Account, Unit-based Compensation	1,241	1,241
Payments Related to Tax Withholding for Share-based Compensation	(119)	(119)
Total partners' capital	516,726	226,301		269,886		11,066			9,743
Total partners' capital	499,566	215,146		266,725		8,302			9,393
Net loss	(49,579)			(11,483)					(1,024)
Payments of Stock Issuance Costs									991
Net loss allocated to limited partner, basic and diluted	(49,579)	(29,659)		(11,483)		(7,446)		(7,446)			(29,659)
Series A convertible preferred unit in-kind distribution and fair value adjustment			$ 837		$ (1,075)		$ 210			$ 28
Class B Convertible unit in-kind distribution		13		6		3			(22)
Equity contribution from Holdings	2	0							2
Partners' Capital Account, Unit-based Compensation	210	210
Contribution from parent allocated by limited partners	4,201			4,201				$ 0	0		$ 0
Payments Related to Tax Withholding for Share-based Compensation	(8)	(8)
Total partners' capital	$ 454,392	$ 184,839		$ 260,512		$ 643			$ 8,398

ORGANIZATION AND DESCRIPTION OF

ORGANIZATION AND DESCRIPTION OF BUSINESS	9 Months Ended
	Sep. 30, 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 54.4% 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. Termination of AMID Transactions On July 29, 2018, we terminated the Agreement and Plan of Merger, dated October 31, 2017, by and among us, our General Partner, American Midstream Partners, LP, a Delaware limited partnership (“AMID”), American Midstream GP, LLC, a Delaware limited liability company and the general partner of AMID (“AMID GP”), and Cherokee Merger Sub LLC, a Delaware limited liability company and wholly owned subsidiary of AMID (“Merger Sub”) as amended by that certain Amendment No. 1 to Merger Agreement, dated as of June 1, 2018, by and among us, our General Partner, AMID, AMID GP and Merger Sub (as amended, the “Merger Agreement”), as a result of the merger contemplated by the Merger Agreement not being completed on or prior to June 15, 2018. As previously disclosed, under the Merger Agreement, we were to merge with and into Merger Sub, with the Partnership surviving the merger as a wholly owned subsidiary of AMID. Simultaneously, on July 29, 2018, Holdings terminated the Contribution Agreement, dated October 31, 2017, by and among Holdings, AMID and AMID GP, as amended by that certain Amendment No. 1 to Contribution Agreement, dated as of June 1, 2018, by and among Holdings, AMID and AMID GP (as amended, the “Contribution Agreement”), as result of the transactions contemplated by the Contribution Agreement not being completed on or prior to June 15, 2018 due to AMID’s Funding Failure (as defined in the Contribution Agreement). Pursuant to the terms of the Contribution Agreement, AMID was obligated to pay Holdings a fee of $17 million as a result of such termination. On August 1, 2018, AMID paid the $17 million termination fee to Holdings, of which $4.2 million was contributed to the Partnership and was used to reimburse the Partnership’s transaction costs. Letter Agreement. In connection with the Merger Agreement and Contribution Agreement, Holdings and the Partnership entered into a Letter Agreement (the “Letter Agreement”) providing for Holdings to 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, including if the Contribution Agreement is terminated in a manner that results in Holdings being entitled to receive the termination fee, or (b) the Merger Agreement is terminated without the prior approval of the conflicts committee of the Partnership under certain specified circumstances. A portion of the termination fee referenced above was used to reimburse the Partnership’s transaction costs. Liquidity Consideration Our future cash flow may be materially adversely affected if the natural gas and NGL volumes connected to our systems decline. 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 and our success in connecting volumes to our systems. 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 intend to capitalize on the improving commercial environment in our key operating areas as we pursue various strategic options to improve our balance sheet. 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 $120 million (then further reduced to $115 million on December 31, 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. On August 10, 2018, we entered into the sixth amendment (the “Sixth Amendment”) to the Third A&R Revolving Credit Agreement which, among other things, reduced the Consolidated Interest Coverage Ratio from 1.50 to 1.00 to 1.25 to 1.00 for the period ending on June 30, 2018. See Note 5. 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, neither of which the Partnership expects, or absent additional amendments to its Third A&R Revolving Credit Agreement (which is due August 4, 2019) or waivers of the March 31, 2019 requirement to comply with the Consolidated Total Leverage Ratio (as defined in the Fifth Amendment) and Consolidated Interest Coverage Ratio (as defined in the Sixth Amendment), the Partnership is not expected to be able to comply with such financial covenants in the next twelve months, which will trigger an event of default under the Senior Credit Facilities (as defined and discussed 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, together with the maturity date of the Third A&R Revolving Credit Agreement being in less than twelve months, 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 we do not comply with the applicable covenants or if our independent registered public accounting firm reports in a subsequent audit report the existence of substantial doubt regarding our ability to continue as a going concern, then an event of default under the Senior Credit Facilities would occur which 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 and for which the Partnership does not have sufficient funds to repay upon an event of default or upon maturity. Management is pursuing all reasonable 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	9 Months Ended
	Sep. 30, 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 Securities Exchange Commission (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 September 30, 2018 and December 31, 2017 , and for the three and nine months ended September 30, 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 and nine months ended September 30, 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. Segments Our chief operating decision-maker is our 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 nine months ended September 30, 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. These changes 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 method 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. In July 2018, the FASB issued an updated accounting pronouncement which permits an entity to apply initially the new leasing standard at the adoption date and recognize a cumulative-effect adjustment to the opening balance sheet of partners’ equity in the period of adoption. We have evaluated the majority of our lease agreements and are developing our implementation plan to assess the impact to our existing financial statement disclosures. The lease pronouncement will become effective beginning in 2019.

NET (LOSS) INCOME PER LIMITED P

NET (LOSS) INCOME PER LIMITED PARTNER UNIT AND DISTRIBUTIONS	9 Months Ended
	Sep. 30, 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 and nine months ended September 30, 2018 and 2017 (in thousands, except unit and per unit data): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net loss $ (14,834 ) $ (19,058 ) $ (49,579 ) $ (50,311 ) General partner unit in-kind distribution (11 ) (20 ) (33 ) (50 ) Net loss attributable to partners $ (14,845 ) $ (19,078 ) $ (49,612 ) $ (50,361 ) General partner's interest (1) $ (308 ) $ (396 ) $ (1,024 ) $ (1,019 ) Class B Convertible limited partner interest (1) (3,487 ) (4,235 ) (11,483 ) (11,058 ) Limited partners' interest (1) Common $ (8,833 ) $ (11,545 ) $ (29,659 ) $ (30,590 ) Subordinated (2,217 ) (2,902 ) (7,446 ) (7,694 ) (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 September 30, Nine Months Ended September 30, Common Units 2018 2017 2018 2017 Interest in net loss $ (8,833 ) $ (11,545 ) $ (29,659 ) $ (30,590 ) Effect of dilutive units - numerator (1) — — — — Dilutive interest in net loss $ (8,833 ) $ (11,545 ) $ (29,659 ) $ (30,590 ) Weighted-average units - basic 48,657,961 48,573,647 48,640,448 48,544,728 Effect of dilutive units - denominator (1) — — — — Weighted-average units - dilutive 48,657,961 48,573,647 48,640,448 48,544,728 Basic and diluted net loss per common unit $ (0.18 ) $ (0.24 ) $ (0.61 ) $ (0.63 ) Three Months Ended September 30, Nine Months Ended September 30, Subordinated Units 2018 2017 2018 2017 Interest in net loss $ (2,217 ) $ (2,902 ) $ (7,446 ) $ (7,694 ) Effect of dilutive units - numerator (1) — — — — Dilutive interest in net loss $ (2,217 ) $ (2,902 ) $ (7,446 ) $ (7,694 ) Weighted-average units - basic 12,213,713 12,213,713 12,213,713 12,213,713 Effect of dilutive units - denominator (1) — — — — Weighted-average units - dilutive 12,213,713 12,213,713 12,213,713 12,213,713 Basic and diluted net loss per subordinated unit $ (0.18 ) $ (0.24 ) $ (0.61 ) $ (0.63 ) (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 87,388 and 86,418 unvested awards granted under the LTIP for the three months ended September 30, 2018 and 2017, respectively. The weighted average units that were not included in the computation of diluted per unit amounts were 230,833 and 46,551 unvested awards granted under the LTIP for the nine months ended September 30, 2018 and 2017, respectively. 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, second and third quarters 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 . Paid In-Kind Distributions Class B Convertible Units. As of September 30, 2018 , the Class B Convertible Units consisted of 19,314,797 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 September 30, 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 November 12, 2018 September 30, 2018 $ 0.3257 338,034 $ 196 6,899 $ 4 August 13, 2018 June 30, 2018 0.3257 332,220 515 6,780 11 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	9 Months Ended
	Sep. 30, 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 September 30, 2018, the fair-value of our term loan was $388.9 million and the fair-value of the Investment Notes (defined in Note 5) was $14.8 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 September 30, 2018 40,000 3.000 % December 31, 2016 January 1, 2019 — 60,000 3.000 % June 30, 2017 June 30, 2019 14 175,000 4.000 % June 30, 2018 June 30, 2019 1 $ 15 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 September 30, 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 September 30, 2018 December 31, 2017 Current interest rate derivative assets $ 15 $ 1 Non-current interest rate derivative assets — 1 Total interest rate derivatives $ 15 $ 2 The realized and unrealized amounts recognized in interest expense associated with derivatives were as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Unrealized loss (gain) on interest rate derivatives $ (12 ) $ 5 $ (13 ) $ — Realized gain on interest rate derivatives — — — (15 )

LONG-LIVED ASSETS

LONG-LIVED ASSETS	9 Months Ended
	Sep. 30, 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) September 30, 2018 December 31, 2017 Pipelines 15-30 $ 574,870 $ 571,730 Gas processing, treating and other plants 15 520,480 520,765 Compressors 5-15 79,093 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 2,863 2,114 Total property, plant and equipment 1,236,949 1,233,249 Accumulated depreciation and amortization (386,927 ) (334,528 ) Total 850,022 898,721 Construction in progress 5,871 2,173 Land and other 13,654 13,653 Property, plant and equipment, net $ 869,547 $ 914,547 Depreciation is provided using the straight-line method based on the estimated useful life of each asset. Depreciation expense for the three and nine months ended September 30, 2018 was $17.8 million and $53.5 million , respectively, and $17.5 million and $53.7 million for the three and nine months ended September 30, 2017, 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, however, during the third quarter of 2018, management elected to restart Bonnie View. Our election to restart Bonnie View has not had a material impact to our third quarter 2018 earnings and cash flows. 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 September 30, 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	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
LONG-TERM DEBT	LONG-TERM DEBT Our outstanding debt and related information at September 30, 2018 and December 31, 2017 are as follows (in thousands): September 30, 2018 December 31, 2017 Revolving credit facility due 2019 $ 83,124 $ 94,555 Term loans due 2021 430,204 433,396 Senior unsecured notes payable due 2019 16,334 — Original issuance discount on term loans due 2021 (893 ) (1,134 ) Total long-term debt (including current portion) 528,769 526,817 Current portion of long-term debt (522,787 ) (4,256 ) Deferred financing costs (5,982 ) (8,295 ) Total long-term debt $ — $ 514,266 Outstanding letters of credit $ 24,861 $ 24,911 Remaining unused borrowings $ 12,015 $ 15,534 Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Weighted average interest rate 7.41 % 6.26 % 7.07 % 6.06 % Average outstanding borrowings $ 530,208 $ 542,578 $ 530,208 $ 548,529 Maximum borrowings $ 530,227 $ 548,080 $ 532,952 $ 561,305 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 $120 million on June 30, 2018 and will be further reduced to $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. Our Consolidated Interest Coverage Ratio was 1.51 to 1.00 as of September 30, 2018; (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 8.61 to 1.00 as of September 30, 2018. On August 10, 2018, we entered into the Sixth Amendment which, among other things, reduced the Consolidated Interest Coverage Ratio from 1.50 to 1.00 to 1.25 to 1.00 for the period ending on June 30, 2018. The Sixth Amendment, notwithstanding, 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 the Third A&R Revolving Credit Agreement (which is due August 4, 2019) or waivers of the March 31, 2019 requirement to comply with the Consolidated Total Leverage Ratio (as defined in the Fifth Amendment) and Consolidated Interest Coverage Ratio (as defined in the Sixth Amendment), the Partnership is not expected to comply with such financial covenants in the next twelve months, which will trigger an event of default under the Senior Credit Facilities. As a result, our expected inability to comply with our financial covenants, together with the expected maturity date of a significant portion of our borrowings within 12 months, we have classified all of our debt as current as of September 30, 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 $1.3 million of PIK interest as of September 30, 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 256 66 Amortization of deferred financing costs (2,569 ) (2,475 ) Deferred financing costs, September 30 $ 5,982 $ 9,065

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Sep. 30, 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 Resources Corp. (“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 January 2019. We believe this matter is without merit and we intend to defend the arbitration vigorously. Because this matter is still in discovery 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 have filed an appeal of this judgment and believe that we have adequate insurance coverage to cover this matter. As a result, during the nine months ended September 30, 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 previously received judgements 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. 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, sought to recover from our subsidiary, Southcross Marketing Co. Ltd., natural gas payments made to us prior to Sherwin’s 2016 bankruptcy. We settled this claim for $0.3 million in July 2018. 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 and $0.4 million for the three and nine months ended September 30, 2018 , respectively, and $0.1 million and $0.4 million for the three and nine months ended September 30, 2017, respectively. Capital leases entered into during the three and nine months ended September 30, 2018, were $0.2 million and $1.5 million , respectively. There were no capital leases entered into during the three months ended September 30, 2017. Capital leases entered into during the nine months ended September 30, 2017 were $0.5 million . The capital lease obligation amounts included in the balance sheets were as follows (in thousands): September 30, 2018 December 31, 2017 Other current liabilities $ 636 $ 410 Other non-current liabilities 1,139 410 Total $ 1,775 $ 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 $1.4 million and $4.2 million for the three and nine months ended September 30, 2018, respectively, and $1.4 million and $4.4 million for the three and nine months ended September 30, 2017, respectively. A rental reimbursement included in our lease agreement associated with the office space we leased in June 2015 of $1.9 million , net of amortization, has been recorded as a deferred liability in our condensed consolidated balance sheets as of September 30, 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	9 Months Ended
	Sep. 30, 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 September 30, Nine Months Ended September 30, 2018 2017 2018 2017 EIG 36 35 108 105 Tailwater 38 36 114 108 Total fees and expenses paid for director services to affiliated entities $ 74 $ 71 $ 222 $ 213 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 September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Reimbursements included in general and administrative expenses $ 2,356 $ 2,189 $ 5,585 $ 9,217 Reimbursements included in operations and maintenance expenses 3,896 3,728 10,893 12,546 Total reimbursements to our General Partner and its affiliates $ 6,252 $ 5,917 $ 16,478 $ 21,763 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 $0.8 million and $1.6 million for the three and nine months ended September 30, 2018 and $0.1 million and $1.4 million for the three and nine months ended September 30, 2017, respectively. We recorded revenues from affiliates of $75.4 million and $187.3 million for the three and nine months ended September 30, 2018 and $48.4 million and $129.5 million for the three and nine months ended September 30, 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 $48.5 million and $33.2 million as of September 30, 2018 and December 31, 2017 , respectively, and accounts payable due to affiliates of $0.1 million and $0.4 million as of September 30, 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 September 30, 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. In connection with the Merger Agreement and Contribution Agreement, Holdings and the Partnership entered into the Letter Agreement (see Note 5 for a description of the Letter Agreement). On July 29, 2018, Holdings terminated the Contribution Agreement as a result of the transactions contemplated thereby not being completed on or prior to June 15, 2018 due to AMID’s Funding Failure (as defined in the Contribution Agreement). Pursuant to the terms of the Contribution Agreement, AMID was obligated to pay Holdings a $17 million termination fee as a result of such termination. On August 1, 2018, AMID paid the $17 million termination fee to Holdings, of which $4.2 million was contributed to the Partnership and was used to reimburse the Partnership’s transaction costs. On October 4, 2018, EPIC Midstream Holdings, LP (“EPIC”) and EPIC Y-Grade Holdings, LP, a subsidiary of EPIC, entered into a definitive equity purchase agreement with Holdings and Holdings Borrower to acquire Robstown, as well as a 57-mile pipeline that enables the Robstown facility to receive natural gas liquids from various pipelines that allow the delivery of fractionated products to several Corpus Christi-area markets. Under the terms of the agreement, EPIC would assume all of the NGL purchase and sale agreements associated with the Robstown fractionator, including those with the Partnership. Since these agreements are expected to remain in place, we do not expect this transaction to have a material effect on the Partnership’s ongoing financial position.

PARTNERS' CAPITAL

PARTNERS' CAPITAL	9 Months Ended
	Sep. 30, 2018
Partners' Capital Notes [Abstract]
PARTNERS' CAPITAL	PARTNERS’ CAPITAL Ownership Our units outstanding as of September 30, 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 44,010 — — — — In-kind distributions and issuances to general partner to maintain 2.0% ownership — — 979,616 — 20,890 Board of director grants 12,739 — — — 260 Units outstanding as of September 30, 2018 22,178,862 26,492,074 19,314,797 12,213,713 1,636,723 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 September 30, 2018, the Class B Convertible Units consist of 19,314,797 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 September 30, 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	9 Months Ended
	Sep. 30, 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) (17,116 ) $ 9.83 Vested units (1) (44,010 ) $ 5.00 Unvested - September 30, 2018 32,502 $ 7.94 (1) The weighted-average fair-value price on the date of vesting for our vested units was $1.55 and $1.67 for the three and nine months ended September 30, 2018. The weighted-average fair-value price on the date of vesting for our units recaptured for tax withholdings was $1.55 and $1.69 for the three and nine months ended September 30, 2018. For the nine months ended September 30, 2018 , we granted awards under the LTIP with a grant date fair-value of $0.1 million which immediately vested on the grant date. As of September 30, 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 September 30, 2018 , we had 5,338,849 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 September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Unit-based compensation $ 40 $ 827 $ 210 $ 1,241 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 September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Matching contributions expensed for employee savings plan $ 145 $ 164 $ 468 $ 555

EQUITY IN JOINT VENTURES

EQUITY IN JOINT VENTURES	9 Months Ended
	Sep. 30, 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 and nine months ended September 30, 2018 and 2017 is as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Revenue T2 Eagle Ford $ 975 $ 854 $ 2,990 $ 3,157 T2 Cogen 84 118 387 233 T2 LaSalle 392 436 1,223 1,220 Net loss T2 Eagle Ford $ (4,670 ) $ (4,904 ) $ (14,010 ) $ (14,714 ) T2 Cogen (910 ) (797 ) (2,666 ) (2,813 ) T2 LaSalle (1,482 ) (1,468 ) (4,444 ) (4,404 ) Our equity in losses of joint venture investments is comprised of the following for the three and nine months ended September 30, 2018 and 2017 (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 T2 Eagle Ford $ (2,335 ) $ (2,452 ) $ (7,005 ) $ (7,357 ) T2 Cogen (455 ) (399 ) (1,333 ) (1,407 ) T2 LaSalle (371 ) (367 ) (1,111 ) (1,101 ) Equity in losses of joint venture investments $ (3,161 ) $ (3,218 ) $ (9,449 ) $ (9,865 ) Our investments in joint ventures is comprised of the following as of September 30, 2018 and December 31, 2017 (in thousands): September 30, 2018 December 31, 2017 T2 Eagle Ford $ 85,598 $ 92,248 T2 Cogen 3,091 4,425 T2 LaSalle 13,963 15,074 Investments in joint ventures $ 102,652 $ 111,747

CONCENTRATION OF CREDIT RISK AN

CONCENTRATION OF CREDIT RISK AND TRADE ACCOUNTS RECEIVABLE	9 Months Ended
	Sep. 30, 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 and nine months ended September 30, 2018 and 2017 represent the following percentages of consolidated revenue: Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Top ten customers 42.6 % 53.0 % 42.7 % 50.2 % The percentage of total consolidated revenue for each customer, excluding affiliates, that exceeded 10% of total revenues for the three and nine months ended September 30, 2018 and 2017 was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Talen Energy Marketing, LLC (a) 13.7 % (a) (a) Calpine Energy Services LP (a) 10.4 % (a) (a) (a) Information is not provided for periods for which the customer or producer was less than 10% of our consolidated revenue. For the nine months ended September 30, 2018 and 2017 , we did not experience significant non-payment for services. We had no allowance for uncollectible accounts receivable at September 30, 2018 .

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	9 Months Ended
	Sep. 30, 2018
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS On October 4, 2018, EPIC and EPIC Y-Grade Holdings, LP, a subsidiary of EPIC, entered into a definitive equity purchase agreement with Holdings and Holdings Borrower to acquire Robstown, as well as a 57-mile pipeline that enables the Robstown facility to receive natural gas liquids from various pipelines that allow the delivery of fractionated products to several Corpus Christi-area markets. See Note 8.

SUPPLEMENTAL INFORMATION

SUPPLEMENTAL INFORMATION	9 Months Ended
	Sep. 30, 2018
Supplemental Cash Flow Elements [Abstract]
SUPPLEMENTAL INFORMATION	SUPPLEMENTAL INFORMATION Supplemental Cash Flow Information (in thousands) Nine Months Ended September 30, 2018 2017 Supplemental Disclosures: Cash paid for interest $ 28,365 $ 26,428 Cash paid for taxes — 4 Supplemental disclosures of non-cash investing and financing activities: Accounts payable related to capital expenditures 652 1,441 Capital lease obligations 380 53 Class B Convertible unit in-kind distributions 1,075 2,447 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 September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Total interest costs $ 11,257 $ 10,045 $ 32,543 $ 29,110 Capitalized interest included in property, plant and equipment, net (99 ) (114 ) (280 ) (440 ) Interest expense $ 11,158 $ 9,931 $ 32,263 $ 28,670 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 September 30, 2018 were as follows: $0.5 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 and $2.0 million for the three and nine months ended September 30, 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 $0.7 million and $1.3 million for the three and nine months ended September 30, 2018 , and $0.8 million and $2.3 million for the for the three and nine months ended September 30. 2017, respectively. Deferred revenue associated with these agreements was $11.2 million and $11.6 million at September 30, 2018 and December 31, 2017, respectively.

BASIS OF PRESENTATION AND SUM_2

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation We prepared this report under the rules and regulations of the Securities Exchange Commission (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 September 30, 2018 and December 31, 2017 , and for the three and nine months ended September 30, 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 and nine months ended September 30, 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 LIMITED_2

NET (LOSS) INCOME PER LIMITED PARTNER UNIT AND DISTRIBUTIONS (Tables)	9 Months Ended
	Sep. 30, 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 and nine months ended September 30, 2018 and 2017 (in thousands, except unit and per unit data): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net loss $ (14,834 ) $ (19,058 ) $ (49,579 ) $ (50,311 ) General partner unit in-kind distribution (11 ) (20 ) (33 ) (50 ) Net loss attributable to partners $ (14,845 ) $ (19,078 ) $ (49,612 ) $ (50,361 ) General partner's interest (1) $ (308 ) $ (396 ) $ (1,024 ) $ (1,019 ) Class B Convertible limited partner interest (1) (3,487 ) (4,235 ) (11,483 ) (11,058 ) Limited partners' interest (1) Common $ (8,833 ) $ (11,545 ) $ (29,659 ) $ (30,590 ) Subordinated (2,217 ) (2,902 ) (7,446 ) (7,694 ) (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 September 30, Nine Months Ended September 30, Common Units 2018 2017 2018 2017 Interest in net loss $ (8,833 ) $ (11,545 ) $ (29,659 ) $ (30,590 ) Effect of dilutive units - numerator (1) — — — — Dilutive interest in net loss $ (8,833 ) $ (11,545 ) $ (29,659 ) $ (30,590 ) Weighted-average units - basic 48,657,961 48,573,647 48,640,448 48,544,728 Effect of dilutive units - denominator (1) — — — — Weighted-average units - dilutive 48,657,961 48,573,647 48,640,448 48,544,728 Basic and diluted net loss per common unit $ (0.18 ) $ (0.24 ) $ (0.61 ) $ (0.63 ) Three Months Ended September 30, Nine Months Ended September 30, Subordinated Units 2018 2017 2018 2017 Interest in net loss $ (2,217 ) $ (2,902 ) $ (7,446 ) $ (7,694 ) Effect of dilutive units - numerator (1) — — — — Dilutive interest in net loss $ (2,217 ) $ (2,902 ) $ (7,446 ) $ (7,694 ) Weighted-average units - basic 12,213,713 12,213,713 12,213,713 12,213,713 Effect of dilutive units - denominator (1) — — — — Weighted-average units - dilutive 12,213,713 12,213,713 12,213,713 12,213,713 Basic and diluted net loss per subordinated unit $ (0.18 ) $ (0.24 ) $ (0.61 ) $ (0.63 ) (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 87,388 and 86,418 unvested awards granted under the LTIP for the three months ended September 30, 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 September 30, 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 November 12, 2018 September 30, 2018 $ 0.3257 338,034 $ 196 6,899 $ 4 August 13, 2018 June 30, 2018 0.3257 332,220 515 6,780 11 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)	9 Months Ended
	Sep. 30, 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 September 30, 2018 December 31, 2017 Current interest rate derivative assets $ 15 $ 1 Non-current interest rate derivative assets — 1 Total interest rate derivatives $ 15 $ 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 September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Unrealized loss (gain) on interest rate derivatives $ (12 ) $ 5 $ (13 ) $ — Realized gain on interest rate derivatives — — — (15 )

LONG-LIVED ASSETS (Tables)

LONG-LIVED ASSETS (Tables)	9 Months Ended
	Sep. 30, 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) September 30, 2018 December 31, 2017 Pipelines 15-30 $ 574,870 $ 571,730 Gas processing, treating and other plants 15 520,480 520,765 Compressors 5-15 79,093 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 2,863 2,114 Total property, plant and equipment 1,236,949 1,233,249 Accumulated depreciation and amortization (386,927 ) (334,528 ) Total 850,022 898,721 Construction in progress 5,871 2,173 Land and other 13,654 13,653 Property, plant and equipment, net $ 869,547 $ 914,547

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	9 Months Ended
	Sep. 30, 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 $120 million on June 30, 2018 and will be further reduced to $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. Our Consolidated Interest Coverage Ratio was 1.51 to 1.00 as of September 30, 2018; (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 8.61 to 1.00 as of September 30, 2018. On August 10, 2018, we entered into the Sixth Amendment which, among other things, reduced the Consolidated Interest Coverage Ratio from 1.50 to 1.00 to 1.25 to 1.00 for the period ending on June 30, 2018. The Sixth Amendment, notwithstanding, 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 the Third A&R Revolving Credit Agreement (which is due August 4, 2019) or waivers of the March 31, 2019 requirement to comply with the Consolidated Total Leverage Ratio (as defined in the Fifth Amendment) and Consolidated Interest Coverage Ratio (as defined in the Sixth Amendment), the Partnership is not expected to comply with such financial covenants in the next twelve months, which will trigger an event of default under the Senior Credit Facilities. As a result, our expected inability to comply with our financial covenants, together with the expected maturity date of a significant portion of our borrowings within 12 months, we have classified all of our debt as current as of September 30, 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 $1.3 million of PIK interest as of September 30, 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 256 66 Amortization of deferred financing costs (2,569 ) (2,475 ) Deferred financing costs, September 30 $ 5,982 $ 9,065

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	9 Months Ended
	Sep. 30, 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): September 30, 2018 December 31, 2017 Other current liabilities $ 636 $ 410 Other non-current liabilities 1,139 410 Total $ 1,775 $ 820

TRANSACTIONS WITH RELATED PAR_2

TRANSACTIONS WITH RELATED PARTIES (Tables)	9 Months Ended
	Sep. 30, 2018
Related Party Transactions [Abstract]
Schedule of Fees, Expenses and Reimbursements Incurred Through Services with Related Parties	We incurred fees and expenses related to the services from our affiliated directors as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 EIG 36 35 108 105 Tailwater 38 36 114 108 Total fees and expenses paid for director services to affiliated entities $ 74 $ 71 $ 222 $ 213 We incurred expenses related to these reimbursements as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Reimbursements included in general and administrative expenses $ 2,356 $ 2,189 $ 5,585 $ 9,217 Reimbursements included in operations and maintenance expenses 3,896 3,728 10,893 12,546 Total reimbursements to our General Partner and its affiliates $ 6,252 $ 5,917 $ 16,478 $ 21,763

INCENTIVE COMPENSATION (Tables)

INCENTIVE COMPENSATION (Tables)	9 Months Ended
	Sep. 30, 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 September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Unit-based compensation $ 40 $ 827 $ 210 $ 1,241
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 September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Matching contributions expensed for employee savings plan $ 145 $ 164 $ 468 $ 555

REVENUES (Tables)

REVENUES (Tables)	9 Months Ended
	Sep. 30, 2018
Revenues [Abstract]
Schedule of revenues by category	Three Months Ended September 30, Nine Months Ended September 30, Contract Type 2018 2017 2018 2017 Sales of natural gas (1) Fixed Spread $ 72,221 $ 105,503 $ 240,096 $ 288,381 Sales of NGLs and condensate (1) Fixed Spread 70,444 40,466 170,528 124,786 Transportation, gathering and processing Fixed Fee 7,780 7,730 24,041 24,487 Producer fees (2) Fixed Fee — 11,324 — 42,227 Treating and compression Fixed Fee 3,416 3,524 11,011 11,200 Other N/A 943 1,931 3,178 2,833 Total revenues $ 154,804 $ 170,478 $ 448,854 $ 493,914

EQUITY IN JOINT VENTURES (Table

EQUITY IN JOINT VENTURES (Tables)	9 Months Ended
	Sep. 30, 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 and nine months ended September 30, 2018 and 2017 is as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Revenue T2 Eagle Ford $ 975 $ 854 $ 2,990 $ 3,157 T2 Cogen 84 118 387 233 T2 LaSalle 392 436 1,223 1,220 Net loss T2 Eagle Ford $ (4,670 ) $ (4,904 ) $ (14,010 ) $ (14,714 ) T2 Cogen (910 ) (797 ) (2,666 ) (2,813 ) T2 LaSalle (1,482 ) (1,468 ) (4,444 ) (4,404 ) Our equity in losses of joint venture investments is comprised of the following for the three and nine months ended September 30, 2018 and 2017 (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 T2 Eagle Ford $ (2,335 ) $ (2,452 ) $ (7,005 ) $ (7,357 ) T2 Cogen (455 ) (399 ) (1,333 ) (1,407 ) T2 LaSalle (371 ) (367 ) (1,111 ) (1,101 ) Equity in losses of joint venture investments $ (3,161 ) $ (3,218 ) $ (9,449 ) $ (9,865 ) Our investments in joint ventures is comprised of the following as of September 30, 2018 and December 31, 2017 (in thousands): September 30, 2018 December 31, 2017 T2 Eagle Ford $ 85,598 $ 92,248 T2 Cogen 3,091 4,425 T2 LaSalle 13,963 15,074 Investments in joint ventures $ 102,652 $ 111,747

CONCENTRATION OF CREDIT RISK _2

CONCENTRATION OF CREDIT RISK AND TRADE ACCOUNTS RECEIVABLE (Tables)	9 Months Ended
	Sep. 30, 2018
Top ten customers
Consolidated revenue concentration
Schedule of consolidated revenue attributed to Formosa and Sherwin	Our top ten customers, excluding affiliates, for the three and nine months ended September 30, 2018 and 2017 represent the following percentages of consolidated revenue: Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Top ten customers 42.6 % 53.0 % 42.7 % 50.2 %

SUPPLEMENTAL INFORMATION (Table

SUPPLEMENTAL INFORMATION (Tables)	9 Months Ended
	Sep. 30, 2018
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	Supplemental Cash Flow Information (in thousands) Nine Months Ended September 30, 2018 2017 Supplemental Disclosures: Cash paid for interest $ 28,365 $ 26,428 Cash paid for taxes — 4 Supplemental disclosures of non-cash investing and financing activities: Accounts payable related to capital expenditures 652 1,441 Capital lease obligations 380 53 Class B Convertible unit in-kind distributions 1,075 2,447
Capitalization of Interest Cost	We incurred the following interest costs (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Total interest costs $ 11,257 $ 10,045 $ 32,543 $ 29,110 Capitalized interest included in property, plant and equipment, net (99 ) (114 ) (280 ) (440 ) Interest expense $ 11,158 $ 9,931 $ 32,263 $ 28,670
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 _2

ORGANIZATION AND DESCRIPTION OF BUSINESS (Details) $ in Millions	Aug. 04, 2014	Sep. 30, 2018USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2016USD ($)	Jun. 30, 2018USD ($)	Sep. 30, 2018USD ($)	Dec. 31, 2016
Business Acquisition [Line Items]
Reduction in total aggregate commitments		$ 115			$ 145		$ 120
Sublimit for letters of credit reduction		$ 50			50
Consolidated Interest Coverage Ratio		2.50					1.51	2.50
Holdings capital commitment					$ 17
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
Reverse termination fee		$ 17		$ 17
Number of reportable segments							one
Consolidated Total Leverage Ratio					5		5
Cumulative Catch-up adjustment recorded for AIC payments received by customers						$ 2.7
Low end of range to be reimbursed for Partnership transaction costs		$ 4
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	100.00%
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		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Business Acquisition [Line Items]
Total revenues	$ 154,804	$ 170,478	$ 448,854	$ 493,914
Revenue from Related Parties	75,417	48,379	187,263	129,458
Business Acquisition, Pro Forma Information [Abstract]
Net loss	(14,834)	(19,058)	(49,579)	$ (50,311)
Class B Convertible Units [Member]
Business Acquisition, Pro Forma Information [Abstract]
Net loss	(3,487)	(4,235)	(11,483)
General Partner [Member]
Business Acquisition, Pro Forma Information [Abstract]
Net loss	$ (308)	$ (396)	$ (1,024)

NET (LOSS) INCOME PER LIMITED_3

NET (LOSS) INCOME PER LIMITED PARTNER UNIT AND DISTRIBUTIONS (Details)	Aug. 04, 2014	Sep. 30, 2018USD ($)$ / sharesshares	Dec. 31, 2017USD ($)$ / sharesshares	Sep. 30, 2017USD ($)$ / sharesshares	Jun. 30, 2017USD ($)$ / sharesshares	Mar. 31, 2017USD ($)$ / shares	Dec. 31, 2016	Sep. 30, 2018USD ($)$ / sharesshares	Sep. 30, 2017USD ($)$ / sharesshares	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)shares	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		87,388		86,418				230,833,000	46,551,000
General partner unit in-kind distribution									$ 50,000
Net loss attributable to partners		$ (14,845,000)		$ (19,078,000)				$ (49,612,000)	(50,361,000)
General partner's interest		(14,834,000)		(19,058,000)				(49,579,000)	(50,311,000)
Limited partners' interest								(49,579,000)	(50,311,000)
General Partner [Member]
Earnings Per Limited Partner Unit
Preferred Units Cumulative Right to Receive Future Cash Distributions		6,899,000	$ 6,549,000	6,436,000	$ 6,325,000	$ 6,216,000		$ 6,899,000	6,436,000	$ 6,780,000	$ 6,663,000
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								$ (991,000)	(1,019,000)
General partner unit in-kind distribution		11,000		20,000				33,000	50,000
General partner's interest		(308,000)		(396,000)				(1,024,000)
Limited partners' interest									(1,006,000)
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		338,034,000	$ 320,890,000	315,370,000	309,946,000	$ 304,615,000		338,034,000	315,370,000	$ 332,220,000	$ 326,506,000
Net Income (Loss) Allocated to General Partners									(11,058,000)
General partner's interest		(3,487,000)		(4,235,000)				(11,483,000)
Limited partners' interest								(11,483,000)	(11,058,000)
Limited Partner, units authorized
Earnings Per Limited Partner Unit
Limited Partner, units outstanding | shares												22,178,862	26,492,074
Limited partners' interest		(8,833,000)		(11,545,000)				(29,659,000)	(30,590,000)
Interest in net loss		(8,833,000)		(11,545,000)				(29,659,000)	(30,590,000)
Dilutive interest in net loss		$ (8,833,000)		$ (11,545,000)				$ (29,659,000)	$ (30,590,000)
Weighted-average units - basic | shares		48,657,961		48,573,647				48,640,448	48,544,728
Weighted-average units - dilutive | shares		48,657,961		48,573,647				48,640,448	48,544,728
Basic and diluted net loss per common unit | $ / shares		$ (0.18)		$ (0.24)				$ (0.61)	$ (0.63)
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		$ (2,217,000)		$ (2,902,000)				$ (7,446,000)	$ (7,694,000)
Interest in net loss		(2,217,000)			(2,902,000)			(7,446,000)	(7,694,000)
Dilutive interest in net loss		$ (2,217,000)			$ (2,902,000)			$ (7,446,000)	$ (7,694,000)
Weighted-average units - basic | shares		12,213,713			12,213,713			12,213,713	12,213,713
Weighted-average units - dilutive | shares		12,213,713			12,213,713			12,213,713	12,213,713
Basic and diluted net loss per common unit | $ / shares		$ (0.18)			$ (0.24)			$ (0.61)	$ (0.63)
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
Common Units [Member] | Limited Partner, units authorized
Earnings Per Limited Partner Unit
Limited partners' interest				$ (11,545,000)
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 LIMITED_4

NET (LOSS) INCOME PER LIMITED PARTNER UNIT AND DISTRIBUTIONS (Distributions) (Details) - USD ($)	Aug. 04, 2014	May 15, 2013	Apr. 12, 2013	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Series A preferred units , PIK distribution earned
In-Kind Distributions (in dollars per unit)												$ (50,000)
Common Units [Member]
Distributions made to Limited Partner [Line Items]
Ownership interest held by general partners (as a percent)	100.00%
Class B Convertible Units [Member]
Series A preferred units , PIK distribution earned
In-Kind Unit Distribution (in dollars)				$ 196,000	$ 515,000	$ 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				338,034,000	332,220,000	326,506,000	320,890,000	315,370,000	309,946,000	304,615,000	$ 338,034,000	315,370,000	$ 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	0	0	11,000,000	15,000,000	0	0
In-Kind Distributions (in dollars per unit)				(11,000)				(20,000)			$ (33,000)	(50,000)
Common units, distribution declared and paid
Preferred Units Cumulative Right to Receive Future Cash Distributions				$ 6,899,000	$ 6,780,000	$ 6,663,000	$ 6,549,000	$ 6,436,000	$ 6,325,000	$ 6,216,000	$ 6,899,000	$ 6,436,000	$ 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							$ 18.61
Class B Convertible Units [Member] | Class B Convertible Units [Member]
Distributions made to Limited Partner [Line Items]
Conversion of Stock, Shares Issued	18,982,577												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	9 Months Ended
	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2016MMBTU	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)
Fair value of financial instruments
Fair value of Term Loan Credit Agreement				$ 388,900,000
Derivative Asset	$ 15,000			15,000		$ 1,000
Derivative, Notional Amount, $175M, June 30, 2019 Maturity Date				$ 175,000,000
Derivative, $175M Cap Interest Rate, 4.00%				4.00%
Unrealized Gain (Loss) on Derivatives				$ 13,000	$ 15,000
Derivative, Fair Value, Net	15			15
Derivative Assets (Liabilities), at Fair Value, Net	(15,000)			(15,000)		$ (2,000)
Fair Value of Senior Unsecured Note Payable				14,800,000
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	(12,000)	$ 5,000
Unrealized Gain (Loss) on Derivatives	$ 0	$ 0
Interest Rate Cap [Member]
Fair value of financial instruments
Gain (Loss) on Sale of Derivatives				(13,000)	0
Unrealized Gain (Loss) on Derivatives				$ 0	$ (15,000)
Interest Rate Cap 3.00% [Member]
Fair value of financial instruments
Derivative, Cap Interest Rate	3.00%			3.00%
Derivative, Notional Amount, $40M, January 1, 2018 Maturity				$ 40,000,000
Derivative, Notional Amount, $40M, July1, 2019 Maturity				60,000,000
Fair Value, Measurements, Recurring [Member] | Interest Rate Cap 3.00% [Member]
Fair value of financial instruments
Derivative, Notional Amount, $175M, June 30, 2019 Maturity Date				0
Interest Rate Cap 3.00%, $40M, July 1, 2018 Maturity Date				0
Interest Rate Cap 3.00%, $40M, January 1, 2018 Maturity				$ 0

FINANCIAL INSTRUMENTS (Details

FINANCIAL INSTRUMENTS (Details 2)	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2016MMBTU	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)
Derivatives
Derivative Asset	$ 15,000			$ 15,000		$ 1,000
Derivative Asset, Noncurrent	0			0		1,000
Unrealized loss				13,000	$ 15,000
Derivative, Fair Value, Net	15			15
Derivative Assets (Liabilities), at Fair Value, Net	15,000			15,000		$ 2,000
Interest Rate Swap [Member]
Derivatives
Unrealized loss	0	$ 0
Realized (loss) on derivatives	$ (12,000)	$ 5,000
Interest rate cap contract
Derivatives
Unrealized loss				0	(15,000)
Realized (loss) on derivatives				$ (13,000)	$ 0
Commodity Swaps
Derivatives
Volume of month-ahead swap contracts (in MMBtu) | MMBTU			0
Interest Rate Cap 3.00% [Member]
Derivatives
Derivative, Cap Interest Rate	3.00%			3.00%

LONG-LIVED ASSETS (Details)

LONG-LIVED ASSETS (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Mar. 31, 2017	Jun. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Property, plant and equipment
Gregory Fire Insurance Deductible			$ 500
Gain on insurance proceeds	$ 0	$ 0	1,500		$ 0	$ 1,500
Intangible Assets, Net (Excluding Goodwill)	1,300				1,300
Total property, plant and equipment	1,236,949				1,236,949		$ 1,233,249
Accumulated depreciation and amortization	(386,927)				(386,927)		(334,528)
Property, plant and equipment, net	869,547				869,547		914,547
Gain (Loss) on Sale of Assets and Asset Impairment Charges	84	(186)			637	5
Depreciation expense	17,787	$ 17,521			53,549	53,673
Net proceeds from sales of assets					$ 693	$ 2,974
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	5,871				$ 5,871		2,173
Pipelines
Property, plant and equipment
Estimated useful life				30 years
Total property, plant and equipment	574,870				574,870		571,730
Gas processing, treating and other plants
Property, plant and equipment
Estimated useful life				15 years
Total property, plant and equipment	520,480				520,480		520,765
Compressors
Property, plant and equipment
Estimated useful life				15 years
Total property, plant and equipment	79,093				79,093		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		49,897
Furniture, fixtures and equipment
Property, plant and equipment
Estimated useful life				5 years
Total property, plant and equipment	9,746				9,746		9,746
Capital lease vehicles
Property, plant and equipment
Total property, plant and equipment	2,863				2,863		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	850,022				850,022		898,721
Land and other
Property, plant and equipment
Property, plant and equipment, net	$ 13,654				$ 13,654		$ 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 ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2016USD ($)	Jun. 30, 2016USD ($)$ / shares	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2015USD ($)
LONG TERM DEBT
NGL purchases from Holdings		$ 800,000			$ 100,000			$ 1,600,000	$ 1,400,000
Consolidated Interest Coverage Ratio		2.50						1.51		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									(2,475,000)
Long-term Debt		528,769,000						$ 528,769,000			$ 526,817,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net		(893,000)						(893,000)			(1,134,000)
Long-term Debt, Current Maturities		522,787,000						522,787,000			4,256,000
Debt Issuance Costs, Net		(5,982,000)			(9,065,000)	$ (11,474,000)		(5,982,000)	(9,065,000)	$ (11,474,000)	(8,295,000)
Deferred Financing Costs, Capitalized During Period								256,000	66,000
Amortization of Debt Issuance Costs and Discounts								(2,569,000)
Long-term Debt, Excluding Current Maturities		0						$ 0			514,266,000
Sublimit for letters of credit reduction		50,000,000				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		$ 200,000,000
Reduction in total aggregate commitments		115,000,000				$ 145,000,000		120,000,000
Average outstanding borrowings		$ 530,208,000			$ 542,578,000			$ 530,208,000	$ 548,529,000
Line of Credit Facility, Interest Rate Description	0.01
Weighted average interest rate		7.41%			6.26%			7.07%	6.06%
Maximum quarterly distributions until the target leverage ratio is achieved (in dollars per share) | $ / shares							$ 0.40
Maximum borrowings		$ 530,227,000			$ 548,080,000			$ 532,952,000	$ 561,305,000
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								1,300,000
General Partner [Member]
LONG TERM DEBT
Line of Credit Facility, Amount Outstanding		24,861,000						24,861,000			24,911,000
Unsecured Debt [Member]
LONG TERM DEBT
Long-term Debt		16,334,000						16,334,000
Credit Facility, due November 2017
LONG TERM DEBT
Long-term Debt		83,124,000						$ 83,124,000			94,555,000
Debt Instrument Leverage Ratio								5
Line of Credit Facility, Remaining Borrowing Capacity		12,015,000						$ 12,015,000			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		$ 430,204,000						$ 430,204,000			$ 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%						2.00%
Eurodollar [Member] | Maximum [Member]
LONG TERM DEBT
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum (Deprecated 2016-01-31)		4.50%						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%						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%						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 CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Purchase commitments
Woodsboro Litigation Accrual			$ 7,700,000
Bankruptcy Claims, Amount of Claims Settled	$ 300,000		300,000
Capital Lease Obligations, Current	636,000		636,000		$ 410
Capital leases
Amortization expense related to the capital leases	100,000		400,000	$ 400,000
Capital Lease Obligations Incurred	200,000		1,500,000	500,000
Operating Leases
Expenses associated with operating leases	1,400,000	$ 1,400,000	4,200,000	$ 4,400,000
Deferred Rent Credit	1,900,000		1,900,000
Capital Lease Obligations, Noncurrent	1,139,000		1,139,000		410
Capital Lease Obligations	$ 1,775,000		$ 1,775,000		$ 820

TRANSACTIONS WITH RELATED PAR_3

TRANSACTIONS WITH RELATED PARTIES (Details)	Mar. 08, 2014	Sep. 30, 2018USD ($)director	Sep. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2018USD ($)director	Jun. 30, 2016USD ($)	Sep. 30, 2018USD ($)director	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)
Related Party Transactions
Management fees incurred		$ 74,000	$ 71,000				$ 222,000	$ 213,000
Number of directors | director					1
Related Party Transaction, Amounts of Transaction		6,252,000	5,917,000				16,478,000	21,763,000
Revenue from Related Parties		75,417,000	48,379,000				187,263,000	129,458,000
Due to Affiliate, Current		36,000			$ 56,000		36,000		$ 378,000
Contractual Agreement, Term	10 years
Due from Affiliate, Current		48,450,000					48,450,000		$ 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				108,000	105,000
Tailwater [Member]
Related Party Transactions
Management fees incurred		$ 38,000	36,000				$ 114,000	108,000
Director [Member]
Related Party Transactions
board member from an affiliated entity | director		2					2
valley wells [Member]
Related Party Transactions
Affiliate Costs								2,281,000
General and Administrative Expense [Member]
Related Party Transactions
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party		$ 2,356,000	2,189,000				$ 5,585,000	9,217,000
Operating Expense [Member]
Related Party Transactions
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party		$ 3,896,000	$ 3,728,000				$ 10,893,000	$ 12,546,000

SERIES A PREFERRED UNITS (Detai

SERIES A PREFERRED UNITS (Details) - shares	Aug. 04, 2014	May 15, 2013	Apr. 12, 2013	Sep. 30, 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	Jun. 30, 2016$ / sharesshares	Sep. 30, 2018USD ($)$ / sharesshares	Dec. 31, 2017USD ($)shares	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)shares	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2015shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		12,739
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				48,502,090		48,636,517
Limited Partner, units authorized				29,544,524		49,672,885
Limited Partner, units outstanding		22,178,862								26,492,074
Common Stock, Shares, Outstanding			22,178,862	22,122,113
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number			44,010
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			979,616
Preferred Units Cumulative Right to Receive Future Cash Distributions | $			$ 338,034,000	$ 320,890,000	$ 332,220,000	$ 326,506,000	$ 315,370,000	$ 309,946,000	$ 304,615,000
Preferred Units, Outstanding			19,314,797	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			20,890
Ownership interest held by general partners (as a percent)	2.00%		2.00%
Preferred Units Cumulative Right to Receive Future Cash Distributions | $			$ 6,899,000	$ 6,549,000	$ 6,780,000	$ 6,663,000	$ 6,436,000	$ 6,325,000	$ 6,216,000
Partners' Capital Account, Units			1,636,723	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)	100.00%
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	18,982,577			17,105,875
TexStar Rich Gas System [Member]
Ownership interest held by general partners (as a percent)	54.00%
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		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	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	$ 1.67		$ 1.67		$ 1.55
Allocated Share-based Compensation Expense	$ 40,000	$ 827,000	$ 210,000	$ 1,241,000
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			(17,116)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Recaptured for Tax Withholding, Weighted Average Grant Date Fair Value			$ 9.83
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	(44,010)		(44,010)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 5		$ 5
Shared-based Compensation Arrangement by Share-based Payment Award, Equity Instruments, Recaptured for Tax Withholding, Vested, Weighted-Average Fair Value Vesting Date	$ 1.69		$ 1.69		$ 1.55
Employee Savings Plan [Member]
Unit based compensation
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 145,000	$ 164,000	$ 468,000	$ 555,000
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	32,502		32,502			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		$ 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		$ 100,000
Units available for issuance (in shares)	5,338,849		5,338,849
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		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues [Abstract]
Producer Fee Revenue, ASC 606 Adjustment	$ 13,000		$ 39,000
Sales of natural gas(1)	72,221	$ 105,503	240,096	$ 288,381
Sales of NGLs and condensate(1)	70,444	40,466	170,528	124,786
Transportation, gathering and processing	7,780	7,730	24,041	24,487
Producer fee revenue	0	11,324	0	42,227
Treating fee revenue	3,416	3,524	11,011	11,200
Other	943	1,931	3,178	2,833
Total revenues (Note 10)	$ 154,804	$ 170,478	$ 448,854	$ 493,914

EQUITY IN JOINT VENTURES (Detai

EQUITY IN JOINT VENTURES (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2018joint_venture	Dec. 31, 2017USD ($)	Aug. 04, 2014
Income (Loss) from Equity Method Investments	$ (3,161)	$ (3,218)	$ (9,449)	$ (9,865)
number of joint ventures | joint_venture					3
Equity Method Investment Summarized Financial Information, Equity	102,652		102,652			$ 111,747
Natural Gas Midstream Revenue	154,804	170,478	448,854	493,914
Net Income (Loss) Attributable to Parent	(14,834)	(19,058)	(49,579)	(50,311)
Revenues	79,387	122,099	261,591	364,456
T2 Eagle Ford [Member]
Income (Loss) from Equity Method Investments	(2,335)	(2,452)	(7,005)	(7,357)
Equity Method Investment Summarized Financial Information, Equity	85,598		85,598			92,248
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	(4,670)	(4,904)	(14,010)	(14,714)
Natural Gas Midstream Revenue	975	854	2,990	3,157
T2 Cogen [Member]
Income (Loss) from Equity Method Investments	(455)	(399)	(1,333)	(1,407)
Equity Method Investment Summarized Financial Information, Equity	3,091		3,091			4,425
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	(910)	(797)	(2,666)	(2,813)
Natural Gas Midstream Revenue	84	118	387	233
T2 LaSalle [Member]
Income (Loss) from Equity Method Investments	(371)	(367)	(1,111)	(1,101)
Equity Method Investment Summarized Financial Information, Equity	13,963		13,963			$ 15,074
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	(1,482)	(1,468)	(4,444)	(4,404)
Natural Gas Midstream Revenue	$ 392	$ 436	$ 1,223	$ 1,220
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 _3

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
	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Jun. 30, 2015	Sep. 30, 2018	Sep. 30, 2017
Consolidated revenue concentration
Number of top customers			10	10
Concentration risk percentage	42.60%	53.00%			42.70%	50.20%

SUBSEQUENT EVENTS (Details) (De

SUBSEQUENT EVENTS (Details) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Subsequent Events [Abstract]
Return of Capital Contributions to T2 Cogen	$ 26

SUPPLEMENTAL INFORMATION (Detai

SUPPLEMENTAL INFORMATION (Details) $ in Thousands	Mar. 08, 2014	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Operating Leased Assets [Line Items]
Interest Paid, Net				$ 28,365	$ 26,428
Income Taxes Paid				0	4
Capital Expenditures Incurred but Not yet Paid				652	1,441
Repayments of Debt and Capital Lease Obligations				380	53
Interest Costs Incurred [Abstract]
Total interest costs		$ 11,257	$ 10,045	32,543	29,110
Capitalized interest included in property, plant and equipment, net		(99)	(114)	(280)	(440)
Interest expense		11,158	9,931	32,263	28,670
Deferred Financing Costs [Roll Forward]
Deferred financing costs, January 1		5,982	9,065	5,982	9,065	$ 5,982	$ 8,295	$ 11,474
Deferred Financing Costs, Capitalized During Period				256	66
Amortization of Debt Issuance Costs and Discounts				2,569
Amortization of deferred financing costs					(2,475)
Deferred financing costs, September 30		5,982	9,065	5,982	9,065
Number of power plants						2
Contractual agreement, term	10 years
Contingent fees		(700)		(2,000)
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability		$ (700)	$ (800)	(1,300)	(2,300)
Deferred Revenue						$ 11,200	$ 11,600
Paid-in-Kind Interest				1,300
Natural Gas Pipeline Contracts [Member]
Deferred Financing Costs [Roll Forward]
Operating Leases, Future Minimum Payments, Due in Two Years						500
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					2,281
Class B Convertible Units [Member]
Deferred Financing Costs [Roll Forward]
Temporary Equity Accretion Preferred Unit In-kind Distribution					(2,447)
Class B Convertible Units [Member] | Class B Convertible Units [Member]
Deferred Financing Costs [Roll Forward]
Temporary Equity Accretion Preferred Unit In-kind Distribution				(1,075)	(2,447)
Limited Partner, units authorized | Class B Convertible Units [Member]
Deferred Financing Costs [Roll Forward]
Temporary Equity Accretion Preferred Unit In-kind Distribution				$ 837	$ 1,905