Evolve Transition Infrastructure (SNMP) 10-Q 10 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	May 07, 2018
Document And Entity Information
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Entity Registrant Name	Sanchez Midstream Partners LP
Entity Central Index Key	1,362,705
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		15,234,576
Entity Current Reporting Status	Yes

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues
Gathering and transportation lease revenues	$ 12,318
Total revenues	18,536	$ 25,807
Operating expenses:
Lease operating expenses	1,971	4,983
Transportation operating expenses	2,847	3,296
Cost of sales		37
Production taxes	322	473
General and administrative	5,165	5,609
Unit-based compensation expense	1,438	540
Depreciation, depletion and amortization	6,628	12,181
Asset impairments		4,688
Accretion expense	126	258
Total operating expenses	18,497	32,065
Other (income) expense
Interest expense, net	2,599	1,883
Earnings from equity investments	(4,272)	(482)
Other expense	270
Total other (income) expenses	(1,403)	1,401
Total expenses	17,094	33,466
Income (loss) before income taxes	1,442	(7,659)
Net income (loss)	1,442	(7,659)
Less:
Preferred unit paid-in-kind distributions		(2,625)
Preferred unit distributions	(8,750)	(7,000)
Preferred unit amortization	(531)	(404)
Net loss attributable to common unitholders	$ (7,839)	$ (17,688)
Net loss per unit
Common units - Basic and Diluted (in dollars per share)	$ (0.53)	$ (1.32)
Weighted Average Units Outstanding, Common Units - Basic and Diluted (in units)	14,738,528	13,400,138
Common units
Other (income) expense
Net income (loss)	$ 1,442
Natural gas
Revenues
Revenue from contracts with customers	473	$ 2,779
Oil
Revenues
Revenue from contracts with customers	3,462	11,350
Natural gas liquid
Revenues
Revenue from contracts with customers	595	467
Gathering and transportation
Revenues
Revenue from contracts with customers	$ 1,688	$ 11,211

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets
Cash and cash equivalents	$ 1,804	$ 321
Accounts receivable	43	495
Accounts receivable - related entities	6,074	13,099
Prepaid expenses	2,604	2,670
Fair value of derivative instruments	447	942
Total current assets	10,972	17,527
Oil and natural gas properties and related equipment
Oil and natural gas properties, equipment and facilities (successful efforts method)	171,041	170,750
Gathering and transportation assets	185,407	184,969
Less: accumulated depreciation, depletion, amortization and impairment	(145,825)	(142,574)
Oil and natural gas properties and equipment, net	210,623	213,145
Other assets
Intangible assets, net	168,801	172,166
Fair value of derivative instruments	790	1,318
Equity investments	121,258	123,715
Other non-current assets	518	552
Total assets	512,962	528,423
Current liabilities
Accounts payable and accrued liabilities	4,321	1,782
Accounts payable and accrued liabilities - related entities	6,891	10,353
Royalties payable	368	371
Fair value of derivative instruments	1,052	756
Other liabilities	127	151
Total current liabilities	12,759	13,413
Other liabilities
Asset retirement obligation	6,488	6,074
Long-term debt, net of debt issuance costs	182,928	187,808
Fair value of derivative instruments	662	273
Other liabilities	6,545	6,251
Total other liabilities	196,623	200,406
Total liabilities	209,382	213,819
Commitments and contingencies (See Note 12)
Mezzanine equity
Class B preferred units, 31,000,887 units issued and outstanding as of March 31, 2018 and December 31, 2017	344,443	343,912
Partners' capital (deficit)
Common units, 15,171,946 and 14,965,134 units issued and outstanding as of March 31, 2018 and December 31, 2017, respectively	(40,863)	(29,308)
Total partners' (deficit)	(40,863)	(29,308)
Total liabilities and partners' capital	$ 512,962	$ 528,423

Condensed Consolidated Balance4

Condensed Consolidated Balance Sheets (Parenthetical) - shares	Mar. 31, 2018	Dec. 31, 2017
Condensed Consolidated Balance Sheets
Class B preferred units, issued	31,000,887	31,000,887
Class B preferred units, outstanding	31,000,887	31,000,887
Units, issued	15,171,946	14,965,134
Units, outstanding	15,171,946	14,965,134

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net income (loss)	$ 1,442	$ (7,659)
Adjustments to reconcile net income (loss) to cash provided by operating activities:
Depreciation, depletion and amortization	3,263	8,769
Amortization of debt issuance costs	131	128
Asset impairments		4,688
Accretion expense	126	258
Distributions (return on investment) from equity investments	6,992	2,010
Equity earnings in affiliate	(4,272)	(482)
Net (gains) losses on commodity derivative contracts	1,937	(6,055)
Net cash settlements received (paid) on commodity derivative contracts	(189)	1,513
Unit-based compensation	738	540
Loss on earnout derivative	270
Amortization of intangible assets	3,365	3,412
Changes in Operating Assets and Liabilities:
Accounts receivable	102	43
Accounts receivable - related entities	7,105	2,951
Prepaid expenses	66	(20)
Other assets	22	83
Accounts payable and accrued liabilities	5,591	(3,092)
Accounts payable and accrued liabilities- related entities	(3,570)	6,226
Royalties payable	(3)	248
Net cash provided by operating activities	23,116	13,561
Cash flows from investing activities:
Final settlement of oil and natural gas properties acquisition		1,468
Development of oil and natural gas properties	(3)	(143)
Proceeds from sale of assets	350
Construction of gathering and transportation assets	(1,160)	(5,786)
Purchases of and contributions to equity affiliates	(263)	(2,122)
Net cash used in investing activities	(1,076)	(6,583)
Cash flows from financing activities:
Payments for offering costs	(50)	(120)
Proceeds from issuance of debt		7,500
Repayment of debt	(5,000)
Distributions to common unitholders	(6,746)	(5,796)
Class B preferred unit cash distributions	(8,750)	(7,000)
Debt issuance costs	(11)	(26)
Net cash provided by (used in) financing activities	(20,557)	(5,442)
Net decrease in cash and cash equivalents	1,483	1,536
Cash and cash equivalents, beginning of period	321	957
Cash and cash equivalents, end of period	1,804	2,493
Supplemental disclosures of cash flow information:
Change in accrued capital expenditures	641	7,158
Asset retirement obligation	288	195
Earnout liability		221
Cash paid during the period for interest	$ 2,300	$ 1,473

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Changes in Partners’ Capital - USD ($) $ in Thousands	Common units	Total
Partner's Capital (Deficit) at Dec. 31, 2016	$ 16,744	$ 16,744
Partner's Capital (Deficit) (in shares) at Dec. 31, 2016	13,447,749
Unit-based compensation programs	$ 3,373	3,373
Unit-based compensation programs (in shares)	217,481
Issuance of common units, net of offering costs	$ 11,228	11,228
Issuance of common units, net of offering costs (in shares)	906,613
Cash distributions to common unit holders	$ (25,192)	(25,192)
Common units issued as Class B Preferred distributions	$ 5,250	5,250
Common units issued as Class B Preferred distributions (in shares)	393,291
Distributions - Class B preferred units	$ (37,671)	(37,671)
Net loss	(3,040)	(3,040)
Partner's Capital (Deficit) at Dec. 31, 2017	$ (29,308)	(29,308)
Partner's Capital (Deficit) (in shares) at Dec. 31, 2017	14,965,134
Unit-based compensation programs	$ 738	738
Unit-based compensation programs (in shares)	(4,166)
Issuance of common units, net of offering costs	$ 2,292	2,292
Issuance of common units, net of offering costs (in shares)	210,978
Cash distributions to common unit holders	$ (6,746)	(6,746)
Distributions - Class B preferred units	(9,281)	(9,281)
Net loss	1,442	1,442
Partner's Capital (Deficit) at Mar. 31, 2018	$ (40,863)	$ (40,863)
Partner's Capital (Deficit) (in shares) at Mar. 31, 2018	15,171,946

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Changes in Partners’ Capital (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Condensed Consolidated Statements of Changes in Partners’ Capital
Offering costs	$ 0.1	$ 0.6

Organization And Business

Organization And Business	3 Months Ended
	Mar. 31, 2018
Organization And Business
Organization And Business	1. ORGANIZATION AND BUSINESS Organization We are a growth-oriented publicly-traded limited partnership focused on the acquisition, development, ownership and operation of midstream and other energy-related assets in North America. The Partnership has ownership stakes in oil and natural gas gathering systems, natural gas pipelines, and a natural gas processing facility, all located in the Western Eagle Ford in South Texas. We also own production assets in Texas, Louisiana and Oklahoma. We have entered into a shared services agreement (the “Services Agreement”) with SP Holdings, LLC, the sole member of our general partner, pursuant to which the Manager provides services that the Partnership requires to operate its business, including overhead, technical, administrative, marketing, accounting, operational, information systems, financial, compliance, insurance, acquisition, disposition and financing services. On June 2, 2017, Sanchez Production Partners LP changed its name to Sanchez Midstream Partners LP. Manager owns the general partner of SNMP and all of SNMP’s incentive distribution rights. Our common units are currently listed on the NYSE American under the symbol “SNMP.”

Basis Of Presentation And Summa

Basis Of Presentation And Summary Of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2018
Basis Of Presentation And Summary Of Significant Accounting Policies
Basis of Presentation and Significant Accounting Policies	2. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation Accounting policies used by us conform to accounting principles generally accepted in the United States of America (“U.S. GAAP”). These unaudited condensed consolidated financial statements include the accounts of us and our wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. We conduct our business activities as two operating segments: the production of oil and natural gas and the midstream business, which includes Western Catarina Midstream (defined in Note 10). Our management evaluates performance based on these two business segments. These unaudited condensed consolidated financial statements have been prepared pursuant to the rules of the SEC. Certain information and footnote disclosures, normally included in annual financial statements prepared in accordance with U.S. GAAP, have been condensed or omitted pursuant to those rules and regulations. We believe that the disclosures made are adequate to make the information presented not misleading. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, necessary to fairly state the financial position, results of operations and cash flows with respect to the interim condensed consolidated financial statements have been included. The results of operations for the interim periods are not necessarily indicative of the results for the entire year. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto of SNMP and its subsidiaries included in our Annual Report on Form 10-K for the year ended December 31, 2017, which was filed with the SEC on March 12, 2018. Recent Accounting Pronouncements From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”), which are adopted by us as of the specified effective date. Unless otherwise discussed, management believes that the impact of recently issued standards, which are not effective, will not have a material impact on our condensed consolidated financial statements upon adoption. In January 2017, the FASB issued Accounting Standards Update (“ASU”) 2017-01 “Business Combinations (Topic 805) - Clarifying the Definition of a Business,” which provides a new framework for determining whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. This ASU is effective for public business entities for annual and interim periods in fiscal years beginning after December 15, 2017. The Partnership adopted this ASU on January 1, 2018, using a prospective method; the clarified definition of a business will be applied by the Partnership to transactions executed subsequent to the effective date. In November 2016, the FASB issued ASU 2016-18 “Statement of Cash Flows (Topic 230): Restricted Cash,” which requires companies to include cash and cash equivalents that have restrictions on withdrawal or use in total cash and cash equivalents on the statement of cash flows. This ASU is now effective for public business entities beginning after December 15, 2017. The Partnership does not currently have restricted cash. In October 2016, the FASB issued ASU 2016-16 “Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory,” which eliminates a current exception in U.S. GAAP to the recognition of the income tax effects of temporary differences that result from intra-entity transfers of non-inventory assets. The intra-entity exception is being eliminated under the ASU. The standard is required to be applied on a modified retrospective basis and is now effective for public business entities for annual and interim periods in fiscal years beginning after December 15, 2017. The adoption of ASU 2016-16 did not have an impact on the Partnership’s unaudited condensed consolidated financial statements and related disclosures. In February 2016, the FASB issued ASU No. 2016-02 “Leases (Topic 842),” effective for annual and interim periods for public companies beginning after December 15, 2018, with a modified retrospective approach to be used for implementation. ASU 2016-02 updates the previous lease guidance by requiring the recognition of a right-to-use asset and lease liability on the statement of financial position for those leases previously classified as operating leases under the old guidance. In addition, ASU 2016-02 updates the criteria for a lessee’s classification of a finance lease. The Partnership will not early adopt this standard and will apply the revised lease rules for our interim and annual reporting periods starting January 1, 2019. The Partnership is currently evaluating the impact of these rules on its consolidated financial statements and has started the assessment process by evaluating the population of leases under the revised definition. The Partnership is also in the process of implementing a lease accounting software to properly account for lease data upon adoption. The adoption of this standard will result in an increase in the assets and liabilities on the Partnership’s consolidated balance sheets. The quantitative impacts of the new standard are dependent on the leases in force at the time of adoption. As a result, the evaluation of the effect of the new standards will extend over future periods. In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606).” In March, April, May and December of 2016, the FASB issued rules clarifying several aspects of the new revenue recognition standard. The new guidance is effective for fiscal years and interim periods beginning after December 15, 2017. This guidance outlines a new, single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. This new revenue recognition model provides a five-step analysis in determining when and how revenue is recognized. The new model will require revenue recognition to depict the transfer of promised goods or services to customers in an amount that reflects the consideration a company expects to receive in exchange for those goods and services. The new standard also requires more detailed disclosures related to the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. The Partnership adopted the standard effective January 1, 2018. For more information, see Note 3 “Revenue Recognition.” Other accounting standards that have been issued by the FASB or other standards-setting bodies are not expected to have a material impact on the Partnership’s financial position, results of operations and cash flows. Estimates The condensed consolidated financial statements are prepared in conformity with U.S. GAAP, which requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying footnotes. These estimates and the underlying assumptions affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities and reported amounts of revenues and expenses. The estimates that are particularly significant to our financial statements include estimates of our reserves of natural gas, NGLs and oil; future cash flows from oil and natural gas properties; depreciation, depletion and amortization; asset retirement obligations; certain revenues and operating expenses; fair values of derivatives; and fair values of assets and liabilities. As fair value is a market-based measurement, it is determined based on the assumptions that market participants would use. These estimates and assumptions are based on management’s best judgment using the data available. Management evaluates its estimates and assumptions on an on-going basis using historical experience and other factors, including the current economic environment, which management believes to be reasonable under the circumstances. Such estimates and assumptions are adjusted when facts and circumstances dictate. As future events and their effects cannot be determined with precision, actual results could differ from the estimates. Any changes in estimates resulting from continuing changes in the economic environment will be reflected in the financial statements in future periods.

Revenue Recognition

Revenue Recognition	3 Months Ended
	Mar. 31, 2018
Revenue Recognition
Revenue Recognition	3. REVENUE RECOGNITION Adoption of Topic 606 Effective January 1, 2018, the Partnership adopted the new Accounting Standards Codification (“ASC”) 606, Revenue from Contracts with Customers, and all the related amendments (collectively referred to as “Topic 606”) to all open contracts using the modified retrospective approach. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. For contracts that have a contract term of one year or less, we elected to utilize the practical expedient permitted under the rules of adoption whereby a Company is not required to disclose the transaction price allocated to remaining performance obligations if the performance obligation is part of a contract that has an original expected duration of one year or less. Adoption of this guidance resulted in financial statement presentation changes whereby revenue from the Gathering Agreement (defined in Note 13 “Related Party Transactions”) and revenue from the Seco Pipeline Transportation Agreement (defined in Note 13 “Related Party Transactions”) are shown as separate line items within our condensed consolidated statement of operations. There was no cumulative adjustment to retained earnings or any other changes to our January 1, 2018 condensed consolidated balance sheet. Revenue from Contracts with Customers Beginning in 2018, we account for revenue from contracts with customers in accordance with Topic 606. The unit of account in Topic 606 is a performance obligation, which is a promise in a contract to transfer to a customer either a distinct good or service (or bundle of goods or services) or a series of distinct goods or services provided over a period of time. Topic 606 requires that a contract’s transaction price, which is the amount of consideration to which an entity expects to be entitled in exchange for transferring promised goods or services to a customer, is to be allocated to each performance obligation in the contract based on relative standalone selling prices and recognized as revenue when (point in time) or as (over time) the performance obligation is satisfied. Disaggregation of Revenue We disaggregate revenue based on type of revenue and product type. In selecting the disaggregation categories, we considered a number of factors, including disclosures presented outside the financial statements, such as in our earnings release and investor presentations, information reviewed internally for evaluating performance, and other factors used by the Partnership or the users of its financial statements to evaluate performance or allocate resources. As such, we have concluded that disaggregating revenue by type of revenue and product type appropriately depicts how the nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factors. Production Segment Our oil, natural gas, and NGL revenue is marketed and sold on our behalf by the respective asset operators. We are not party to the contracts with the third-party customers and as such, this revenue is not accounted for under Topic 606. We are alternatively party to joint operating agreements, which we account for under ASC 808, and revenue for these arrangements is recognized based on the information provided to us by the operators. We additionally recognize and present changes in the fair value of our commodity derivative instruments within natural gas sales and oil sales in the condensed consolidated statements of operations. As this income is accounted for under ASC 815, Derivatives and Hedging, it is not subject to Topic 606. Midstream Segment The Seco Pipeline Transportation Agreement is our only contract that we account for under Topic 606. The Catarina Midstream Gathering Agreement was classified as an operating lease at inception, and as such, the contract is accounted for under ASC 840, Leases, and is depicted as Gathering and transportation lease revenue in our condensed consolidated statement of operations. Both of these contracts are further discussed in Note 13, “Related Party Transactions.” We additionally recognize income associated with our joint ventures with Targa Resources Corp. (NYSE: TRGP) (“Targa”), Carnero Gathering (defined in Note 11 “Investments”), and Carnero Processing (defined in Note 11 “Investments”) . We account for these as unconsolidated equity method investments that are not in the scope of Topic 606, and our share of earnings is reported as earnings from equity investments in our condensed consolidated statements of operations. Earnings from these equity method investments are classified within the midstream operating segment in Note 17 “Reporting Segments”, and are further discussed in Note 11 “Investments.” We recognized revenue of $18.5 million for three months ended March 31, 2018. The following table displays revenue disaggregated by type of revenue and product type (in thousands): For the Three Months Ended March 31, 2018 Production Midstream Total Revenues: Natural gas sales $ 473 $ — $ 473 Oil sales 3,462 — 3,462 Natural gas liquid sales 595 — 595 Gathering and transportation sales — 1,688 1,688 Gathering and transportation lease revenues — 12,318 12,318 Total revenues $ 4,530 $ 14,006 $ 18,536 Performance Obligations Under the Transportation Agreement, we agreed to provide transportation services of certain quantities of natural gas from the receipt point to the delivery point. Each MMBtu of natural gas transported is distinct and the transportation services performed on each distinct molecule of product is substantially the same in nature. As such, we applied the series guidance and treat these services as a single performance obligation satisfied over time using volumes delivered as the measure of progress. The Transportation Agreement requires payment within 30 days following the calendar month of delivery. The Transportation Agreement contains variable consideration in the form of volume variability. As the distinct goods or services (rather than the series) are considered for the purpose of allocating variable consideration, we have taken the optional exception under ASC 606-10-50-14A(b) which is available only for wholly unsatisfied performance obligations for which the criteria in ASC 606-10-32-40 have been met. Under this exception, neither estimation of variable consideration nor disclosure of the transaction price allocated to the remaining performance obligations is required. Revenue is alternatively recognized in the period that control is transferred to the customer and the respective variable component of the total transaction price is resolved. For forms of variable consideration that are not associated with a specific volume (such as late payment fees) and thus do not meet allocation exception, estimation is required. These fees, however, are immaterial to our consolidated financial statements and have a low probability of occurrence. As significant reversals of revenue due to this variability are not probable, no estimation is required. Contract Balances Under our sales contracts, we invoice customers after our performance obligations have been satisfied, at which point payment is unconditional. Accordingly, our contracts do not give rise to contract assets or liabilities under Reconciliation of Statement of Operations In accordance with the new revenue standard requirements, the disclosure of the impact of adoption on our condensed consolidated statement of operations is as follows (in thousands): For the Three Months Ended March 31, 2018 As reported Balances without Adoption Topic 606 Effect of change Higher/(Lower) Statement of Operations Gathering and transportation sales $ 1,688 $ 14,006 $ (12,318) Gathering and transportation lease revenues 12,318 — 12,318 Net earnings $ 14,006 $ 14,006 $ — We expect the impact of the adoption of the new standard to be immaterial to our net income (loss) on an ongoing basis.

Acquisitions and Divestitures

Acquisitions and Divestitures	3 Months Ended
	Mar. 31, 2018
Acquisitions and Divestitures
Acquisitions and Divestitures	4. ACQUISITIONS AND DIVESTITURES Our acquisitions are accounted for under the acquisition method of accounting in accordance with ASC Topic 805, “Business Combinations.” A business combination may result in the recognition of a gain or goodwill based on the measurement of the fair value of the assets acquired at the acquisition date as compared to the fair value of consideration transferred, adjusted for purchase price adjustments. The initial accounting for acquisitions may not be complete and adjustments to provisional amounts, or recognition of additional assets acquired or liabilities assumed, may occur as more detailed analyses are completed and additional information is obtained about the facts and circumstances that existed as of the acquisition dates. The results of operations of the properties obtained through our acquisitions have been included in the condensed consolidated financial statements since the closing dates of the acquisitions. Texas Production Divestiture In October 2017, we entered into a purchase and sale agreement to sell specified oil and gas wells, leases and other associated assets and interests located in Texas (the “Texas Production Assets”) for cash consideration of approximately $6.3 million (the “Texas Production Divestiture”). In addition, the buyer agreed to assume all obligations relating to the assets, including all plugging and abandonment costs relating to the assets, that arise on or after October 1, 2017. The Texas Production Divestiture closed November 13, 2017, and we recorded a gain of approximately $1.4 million on the sale during the fourth quarter of 2017. Non-Operated Production Divestiture In July 2017, we entered into an agreement to assign certain non-operated production assets located in Oklahoma, as well as our equity interests in the entities that owned the assets, in exchange for agreeing upon the apportionment of certain shared litigation costs. The assignment was effective as of July 14, 2017. Oklahoma Production Divestiture In May 2017, we entered into a purchase and sale agreement to sell all of the Partnership’s equity interests in the entities that owned our remaining operated Oklahoma production assets for cash consideration of $5.5 million, and assumption by the buyer of all obligations relating to the assets arising after the closing date and all plugging and abandonment costs relating to the assets arising prior to the closing date (the “Oklahoma Production Divestiture”). The Oklahoma Production Divestiture closed July 17, 2017, and we recorded a gain of $2.4 million on the sale during the third quarter of 2017.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2018
Fair Value Measurements
Fair Value Measurements	5. FAIR VALUE MEASUREMENTS Measurements of fair value of derivative instruments are classified according to the fair value hierarchy, which prioritizes the inputs to the valuation techniques used to measure fair value. Fair value is the price that would be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value measurements are classified and disclosed in one of the following categories: Level 1: Measured based on unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. Active markets are considered those in which transactions for the assets or liabilities occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2: Measured based on quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability. Substantially all of these inputs are observable in the marketplace throughout the term of the instrument, can be derived from observable data, or supported by observable levels at which transactions are executed in the marketplace. Level 3: Measured based on prices or valuation models that require inputs that are both significant to the fair value measurement and less observable from objective sources (i.e., supported by little or no market activity). Financial assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurement . Management's assessment of the significance of a particular input to the fair value measurement requires judgment, and may affect the valuation of the fair value of assets and liabilities and their placement within the fair value hierarchy levels. The following table summarizes the fair value of our assets and liabilities that were accounted for at fair value on a recurring basis as of March 31, 2018 (in thousands): Fair Value Measurements at March 31, 2018 Active Markets for Observable Identical Assets Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Fair Value Commodity derivative instrument Derivative liability $ — $ (477) $ — $ (477) Midstream derivative instrument Earnout derivative liability — — (6,672) (6,672) Total $ — $ (477) $ (6,672) $ (7,149) The following table summarizes the fair value of our assets and liabilities that were accounted for at fair value on a recurring basis as of December 31, 2017 (in thousands): Fair Value Measurements at December 31, 2017 Active Markets for Observable Identical Assets Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Fair Value Commodity derivative instrument Derivative assets $ — $ 1,231 $ — $ 1,231 Midstream derivative instrument Earnout derivative liability — — (6,402) (6,402) Total $ — $ 1,231 $ (6,402) $ (5,171) As of March 31, 2018, and December 31, 2017, the estimated fair value of cash and cash equivalents, accounts receivable, other current assets and current liabilities approximated their carrying value due to their short-term nature. Fair Value on a Non-Recurring Basis The Partnership follows the provisions of ASC Topic 820-10 for nonfinancial assets and liabilities measured at fair value on a non-recurring basis. The fair value measurements of assets acquired and liabilities assumed are based on inputs that are not observable in the market and therefore represent Level 3 inputs under the fair value hierarchy. We periodically review oil and natural gas properties for impairment when facts and circumstances indicate that their carrying values may not be recoverable. A reconciliation of the beginning and ending balances of the Partnership’s asset retirement obligations is presented in Note 9, “Asset Retirement Obligation.” The following table summarizes the non-recurring fair value measurements of our assets as of March 31, 2018 (in thousands): Fair Value Measurements at March 31, 2018 Active Markets for Observable Identical Assets Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Impairment $ — $ — $ — Total net assets $ — $ — $ — The following table summarizes the non-recurring fair value measurements of our assets as of December 31, 2017 (in thousands): Fair Value Measurements at December 31, 2017 Active Markets for Observable Identical Assets Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Impairment (a) $ — $ — $ 7,277 Total net assets $ — $ — $ 7,277 (a) During the year ended December 31, 2017, we recorded a non-cash impairment charge of $4.7 million to impair our producing oil and natural gas properties acquired in the Production Acquisition (defined in Note 8 “Oil and Natural Gas Properties”). The carrying values of the impaired properties were reduced to a fair value of $7.3 million, estimated using inputs characteristic of a Level 3 fair value measurement. The fair values of oil and natural gas properties were measured using valuation techniques that convert future cash flows to a single discounted amount. Significant inputs to the valuation of oil and natural gas properties include estimates of: (i) reserves; (ii) future operating and development costs; (iii) future commodity prices; (iv) estimated future cash flows; and (v) a market-based weighted average cost of capital rate. These inputs require significant judgments and estimates by the Partnership’s management at the time of the valuation and are the most sensitive and subject to change. Fair Value of Financial Instruments Fair value guidance requires certain fair value disclosures, such as those on our debt and derivatives, to be presented in both interim and annual reports. The estimated fair value amounts of financial instruments have been determined using available market information and valuation methodologies described below. Credit Agreement – We believe that the carrying value of long-term debt for our Credit Agreement (defined Note 7 “Long-Term Debt”) approximates its fair value because the interest rates on the debt approximate market interest rates for debt with similar terms. The debt is classified as a Level 2 input in the fair value hierarchy and represents the amount at which the instrument could be valued in an exchange during a current transaction between willing parties. Our Credit Agreement is discussed further in Note 7, “Long-Term Debt.” Derivative Instruments – The income valuation approach, which involves discounting estimated cash flows, is primarily used to determine recurring fair value measurements of our derivative instruments classified as Level 2 inputs. Our commodity derivatives are valued using the terms of the individual derivative contracts with our counterparties, expected future levels of oil and natural gas prices and an appropriate discount rate. Our interest rate derivatives are valued using the terms of the individual derivative contracts with our counterparties, expected future levels of the LIBOR interest rates and an appropriate discount rate. We did not have any interest rate derivatives as of March 31, 2018. We prioritize the use of the highest level inputs available in determining fair value such that fair value measurements are determined using the highest and best use as determined by market participants and the assumptions that they would use in determining fair value. Earnout Derivative – As part of the Carnero Gathering Transaction (defined in Note 11 “Investments”), we are required to pay Sanchez Energy an earnout based on natural gas received above a threshold volume and tariff at Carnero Gathering, LLC’s delivery points from Sanchez Energy and other producers. The earnout derivative was valued through the use of a Monte Carlo simulation model which utilized observable inputs such as the earnout price and volume commitment, as well as unobservable inputs related to the weighted probabilities of various throughput scenarios. We have therefore classified the fair value measurements of our earnout derivative as Level 3 inputs and currently present it within the other liabilities lines in the condensed consolidated balance sheets. The following table sets forth a reconciliation of changes in the fair value of the Partnership's earnout derivative classified as Level 3 in the fair value hierarchy for the three months ended March 31, 2018 and year ended Dec ember 31 , 2017 (in thousands): Three Months Ended Year Ended March 31, 2018 December 31, 2017 Beginning balance $ (6,402) $ (4,270) Initial fair value of earnout derivative — 221 Loss on earnout derivative (270) (2,353) Ending balance $ (6,672) $ (6,402) Loss included in earnings related to derivatives still held as of March 31, 2018 and December 31, 2017, respectively $ (270) $ (2,353)

Derivative And Financial Instru

Derivative And Financial Instruments	3 Months Ended
	Mar. 31, 2018
Derivative And Financial Instruments
Derivative And Financial Instruments	6. DERIVATIVE AND FINANCIAL INSTRUMENTS To reduce the impact of fluctuations in oil and natural gas prices on our revenues, we periodically enter into derivative contracts with respect to a portion of our projected oil and natural gas production through various transactions that fix or modify the future prices to be realized. These hedging activities are intended to support oil and natural gas prices at targeted levels and to manage exposure to oil and natural gas price fluctuations. It is never our intention to enter into derivative contracts for speculative trading purposes. Under ASC Topic 815, “Derivatives and Hedging,” all derivative instruments are recorded on the condensed consolidated balance sheets at fair value as either short-term or long-term assets or liabilities based on their anticipated settlement date. We will net derivative assets and liabilities for counterparties where we have a legal right of offset. Changes in the derivatives’ fair values are recognized currently in earnings unless specific hedge accounting criteria are met. We have not elected to designate any of our current derivative contracts as hedges; however, changes in the fair value of all of our derivative instruments are recognized in earnings and included in natural gas sales and oil sales in the condensed consolidated statements of operations. As of March 31, 2018, we had the following derivative contracts in place for the periods indicated, all of which are accounted for as mark-to-market activities: Fixed Price Basis Swaps – West Texas Intermediate (WTI) Three Months Ended (volume in Bbls) March 31, June 30, September 30, December 31, Total Average Average Average Average Average Volume Price Volume Price Volume Price Volume Price Volume Price 2018 — $ — 66,432 $ 59.71 62,840 $ 59.78 59,704 $ 59.84 188,976 $ 59.77 2019 62,528 $ 60.41 59,552 $ 60.44 57,024 $ 60.48 54,824 $ 60.52 233,928 $ 60.46 2020 52,776 $ 53.50 50,960 $ 53.50 49,224 $ 53.50 47,624 $ 53.50 200,584 $ 53.50 623,488 Fixed Price Swaps—NYMEX (Henry Hub) Three Months Ended (volume in MMBtu) March 31, June 30, September 30, December 31, Total Average Average Average Average Average Volume Price Volume Price Volume Price Volume Price Volume Price 2018 — $ — 126,600 $ 3.00 121,600 $ 3.00 117,040 $ 3.00 365,240 $ 3.00 2019 119,832 $ 2.85 115,784 $ 2.85 112,032 $ 2.85 108,552 $ 2.85 456,200 $ 2.85 2020 105,104 $ 2.85 102,008 $ 2.85 99,136 $ 2.85 96,200 $ 2.85 402,448 $ 2.85 1,223,888 The following table sets forth a reconciliation of the changes in fair value of the Partnership’s commodity derivatives for the three months ended March 31, 2018 and the year ended December 31, 2017 (in thousands): Three Months Ended Year Ended March 31, 2018 December 31, 2017 Beginning fair value of commodity derivatives $ 1,231 $ 6,436 Net gains (losses) on crude oil derivatives (1,939) 3,284 Net gains on natural gas derivatives 2 663 Net settlements paid (received) on derivative contracts: Oil 229 (6,422) Natural gas — (2,730) Ending fair value of commodity derivatives $ (477) $ 1,231 The effect of derivative instruments on our condensed consolidated statements of operations was as follows (in thousands): Location of Gain(Loss) Three Months Ended March 31, Derivative Type in Income 2018 2017 Commodity – Mark-to-Market Oil sales $ (1,939) $ 5,495 Commodity – Mark-to-Market Natural gas sales 2 560 $ (1,937) $ 6,055 Derivative instruments expose us to counterparty credit risk. Our commodity derivative instruments are currently contracted with four counterparties. We generally execute commodity derivative instruments under master agreements which allow us, in the event of default, to elect early termination of all contracts with the defaulting counterparty. If we choose to elect early termination, all asset and liability positions with the defaulting counterparty would be net cash settled at the time of election. We include a measure of counterparty credit risk in our estimates of the fair values of derivative instruments. In August 2017, we repositioned certain of our crude oil and natural gas hedges in anticipation of the sale of the Texas Production Assets and, in the process, received $3.6 million in net cash from the counterparties on those hedges. As of March 31, 2018, and December 31, 2017, the impact of non-performance credit risk on the valuation of our derivative instruments was not significant. Earnout Derivative Refer to Note 5 “Fair Value Measurements”.

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2018
Long-Term Debt
Long-Term Debt	7. LONG-TERM DEBT We have entered into a credit facility with Royal Bank of Canada, as administrative agent and collateral agent, and the lenders party thereto (the “Credit Agreement”). The Credit Agreement provides a maximum commitment of $500.0 million and has a maturity date of March 31, 2020. Borrowings under the Credit Agreement are secured by various mortgages of oil and natural gas properties that we own as well as various security and pledge agreements among the Partnership and certain of its subsidiaries and the administrative agent. The amount available for borrowing at any one time under the Credit Agreement is limited to the borrowing base for our midstream assets and our oil and natural gas properties. Borrowings under the Credit Agreement are available for direct investment in oil and natural gas properties, acquisitions, and working capital and general business purposes. The Credit Agreement has a sub-limit of $15.0 million which may be used for the issuance of letters of credit. The initial borrowing base under the Credit Agreement was $200.0 million. The borrowing base for the credit available for the upstream oil and gas properties is re-determined semi-annually in the second and fourth quarters of the year, and may be re-determined at our request more frequently and by the lenders, in their sole discretion, based on reserve reports as prepared by petroleum engineers, using, among other things, the oil and natural gas pricing prevailing at such time. The borrowing base for the credit available for our midstream properties is equal to the rolling four quarter EBITDA of our midstream operations and the amount of distributions received from joint ventures multiplied by 5.0 initially, 4.75 for the second full quarter after the acquisition of Western Catarina Midstream and 4.5 thereafter. Outstanding borrowings in excess of our borrowing base must be repaid or we must pledge other oil and natural gas properties as additional collateral. We may elect to pay any borrowing base deficiency in three equal monthly installments such that the deficiency is eliminated in a period of three months. Any increase in our borrowing base must be approved by all of the lenders. As of March 31, 2018, the borrowing base under the Credit Agreement was $249.3 million, with an elected commitment amount of $200.0 million, and w e had $184.0 million of debt outstanding under the facility, leaving us with $16.0 million in unused borrowing capacity. There were no letters of credit outstanding under our Credit Agreement as of March 31, 2018. Our Credit Agreement matures on March 31, 2020. At our election, interest for borrowings under the Credit Agreement are determined by reference to (i) the London interbank rate (“LIBOR”) plus an applicable margin between 2.25% and 3.25% per annum based on utilization or (ii) a domestic bank rate (“ABR”) plus an applicable margin between 1.25% and 2.25% per annum based on utilization plus (iii) a commitment fee of 0.500% per annum based on the unutilized borrowing base. Interest on the borrowings for ABR loans and the commitment fee are generally payable quarterly. Interest on the borrowings for LIBOR loans are generally payable at the applicable maturity date. The Credit Agreement contains various covenants that limit, among other things, our ability to incur certain indebtedness, grant certain liens, merge or consolidate, sell all or substantially all of our assets, make certain loans, acquisitions, capital expenditures and investments, and pay distributions. In addition, we are required to maintain the following financial covenants: · current assets to current liabilities of at least 1.0 to 1.0 at all times; · senior secured net debt to consolidated adjusted EBITDA for the last twelve months, as of the last day of any fiscal quarter, of not greater than 4.5 to 1.0 if the adjusted EBITDA of our midstream operations equals or exceeds one-third of total Adjusted EBITDA or 4.0 to 1.0 if the adjusted EBITDA of our midstream operations is less than one-third of total adjusted EBITDA; and · minimum interest coverage ratio of at least 2.5 to 1.0 if the adjusted EBITDA of our midstream operations is greater than one-third of our total adjusted EBITDA. The Credit Agreement also includes customary events of default, including events of default relating to non-payment of principal, interest or fees, inaccuracy of representations and warranties when made or when deemed made, violation of covenants, cross-defaults, bankruptcy and insolvency events, certain unsatisfied judgments, loan documents not being valid and a change in control. A change in control is generally defined as the occurrence of one of the following events: (i) our existing general partner ceases to be our sole general partner or (ii) certain specified persons shall cease to own more than 50% of the equity interests of our general partner or shall cease to control our general partner. If an event of default occurs, the lenders will be able to accelerate the maturity of the Credit Agreement and exercise other rights and remedies. The Credit Agreement limits our ability to pay distributions to unitholders. We have the ability to pay distributions to unitholders from available cash, including cash from borrowings under the Credit Agreement , as long as no event of default exists and provided that no distributions to unitholders may be made if the borrowings outstanding, net of available cash, under the Credit Agreement exceed 90% of the borrowing base, after giving effect to the proposed distribution. Our available cash is reduced by any cash reserves established by the board of directors of our general partner for the proper conduct of our business and the payment of fees and expenses. At March 31, 2018 , we were in compliance with the financial covenants contained in the Credit Agreement . We monitor compliance on an ongoing basis. If we are unable to remain in compliance with the financial covenants contained in our Credit Agreement or maintain the required ratios discussed above, the lenders could call an event of default and accelerate the outstanding debt under the terms of the Credit Agreement , such that our outstanding debt could become then due and payable. We may request waivers of compliance for any violation of a financial covenant from the lenders, but there is no assurance that such waivers would be granted. Debt Issuance Costs As of March 31, 2018, and December 31, 2017 , our unamortized debt issuance costs were $1.1 million and $1.2 million, respectively. These costs are amortized to interest expense in our condensed consolidated statements of operations over the life of our Credit Agreement . Amortization of debt issuance costs recorded during each of the three months ended March 31, 2018 and 2017 were $0.1 million.

Oil And Natural Gas Properties

Oil And Natural Gas Properties And Related Equipment	3 Months Ended
	Mar. 31, 2018
Oil And Natural Gas Properties And Related Equipment.
Oil And Natural Gas Properties And Related Equipment	8. OIL AND NATURAL GAS PROPERTIES AND RELATED EQUIPMENT Gathering and transportation assets consisted of the following (in thousands): March 31, December 31, 2018 2017 Gathering and transportation assets Midstream assets $ 185,407 $ 184,969 Less: Accumulated depreciation and amortization (28,770) (26,870) Total gathering and transportation assets $ 156,637 $ 158,099 Oil and natural gas properties consisted of the following (in thousands): March 31, December 31, 2018 2017 Oil and natural gas properties and related equipment Proved property $ 171,041 $ 170,750 Less: Accumulated depreciation, depletion, amortization and impairments (117,055) (115,704) Oil and natural gas properties and equipment, net $ 53,986 $ 55,046 Oil and Natural Gas Properties. We follow the successful efforts method of accounting for our oil and natural gas production activities. Under this method of accounting, costs relating to leasehold acquisition, property acquisition and the development of proved areas are capitalized when incurred. If proved reserves are found on an undeveloped property, leasehold cost is transferred to proved properties. Depreciation, Depletion and Amortization . Depreciation and depletion of producing oil and natural gas properties is recorded at the field level, based on the units-of-production method. Unit rates are computed for unamortized drilling and development costs using proved developed reserves and for unamortized leasehold costs using all proved reserves. All other properties, including the gathering and transportation assets, are stated at historical acquisition cost, net of any impairments, and are depreciated using the straight-line method over the useful lives of the assets, which range from 3 to 15 years for furniture and equipment, and up to 36 years for gathering facilities. Depreciation, depletion, amortization and impairments consisted of the following (in thousands): Three Months Ended March 31, 2018 2017 Depreciation, depletion and amortization of oil and natural gas-related assets $ 1,363 $ 3,234 Depreciation and amortization of gathering and transportation related assets 1,900 5,535 Amortization of intangible assets 3,365 3,412 Total Depreciation, depletion and amortization 6,628 12,181 Asset impairments — 4,688 Total $ 6,628 $ 16,869 Impairment of Oil and Natural Gas Properties and Other Non-Current Assets. Oil and natural gas properties are reviewed for impairment on a field-by-field basis when facts and circumstances indicate that their carrying value may not be recoverable. We assess impairment of capitalized costs of proved oil and natural gas properties by comparing net capitalized costs to estimated undiscounted future net cash flows using expected prices. If net capitalized costs exceed estimated undiscounted future net cash flows, the measurement of impairment is based on estimated fair value, which would consider estimated future discounted cash flows. The cash flow estimates are based upon reserve reports using future expected oil and natural gas prices adjusted for basis differentials. Other significant inputs, besides reserves, used to determine the fair values of proved properties include estimates of: (i) future operating and development costs; (ii) future commodity prices; and (iii) a market-based weighted average cost of capital rate. These inputs require significant judgments and estimates by the Partnership’s management at the time of the valuation and are the most sensitive and subject to change. Cash flow estimates for impairment testing exclude derivative instruments. The recoverability of gathering and transportation assets is evaluated when facts or circumstances indicate that their carrying value may not be recoverable. Asset recoverability is measured by comparing the carrying value of the asset or asset group with its expected future pre-tax undiscounted cash flows. These cash flow estimates require us to make projections and assumptions for many years into the future for pricing, demand, competition, operating cost and other factors. If the carrying amount exceeds the expected future undiscounted cash flows, we recognize an impairment equal to the excess of net book value over fair value. The determination of the fair value using present value techniques requires us to make projections and assumptions regarding the probability of a range of outcomes and the rates of interest used in the present value calculations. Any changes we make to these projections and assumptions could result in significant revisions to our evaluation of recoverability of our gathering and transportation assets and the recognition of additional impairments. Upon disposition or retirement of gathering and transportation assets, any gain or loss is recorded to operations. For the three months ended March 31, 2018, we recorded no impairment charges. For the three months ended March 31, 2017, we recorded non-cash charges of $4.7 million to impair certain of our producing oil and natural gas properties in Texas acquired as part of the acquisition in November 2016, where we completed the acquisition from SN Cotulla Assets, LLC and SN Palmetto, LLC, each a wholly-owned subsidiary of Sanchez Energy, of working interests in 23 producing Eagle Ford Shale wellbores located in Dimmit and Zavala counties in South Texas together with escalating working interests in an additional 11 producing wellbores located in the Palmetto Field in Gonzales County, Texas (together, the “Production Acquisition”). Asset Retirement Costs. As described in Note 9 “Asset Retirement Obligation”, estimated asset retirement costs (“ARC”) are recognized when the asset is acquired or placed in service and are amortized over proved developed reserves using the units-of-production method for production assets and the straight-line method for midstream assets. Asset retirement costs are estimated by our engineers using existing regulatory requirements and anticipated future inflation rates.

Asset Retirement Obligation

Asset Retirement Obligation	3 Months Ended
	Mar. 31, 2018
Asset Retirement Obligation
Asset Retirement Obligation	9. ASSET RETIREMENT OBLIGATION We recognize the fair value of a liability for an asset retirement obligation (“ARO”) in the period in which it is incurred if a reasonable estimate of fair value can be made. Each period, we accrete the ARO to its then present value. The associated ARC is capitalized as part of the carrying amount of our oil and natural gas properties, equipment and facilities or gathering and transportation assets. Subsequently, the ARC is depreciated using the units-of-production method for production assets and the straight-line method for midstream assets. The AROs recorded by us relate to the plugging and abandonment of oil and natural gas wells, and decommissioning of oil and natural gas gathering and other facilities. Inherent in the fair value calculation of ARO are numerous assumptions and judgments including the ultimate settlement amounts, inflation factors, credit adjusted discount rates, timing of settlement and changes in the legal, regulatory, environmental and political environments. To the extent future revisions to these assumptions result in adjustments to the recorded fair value of the existing ARO, a corresponding adjustment is made to the ARC capitalized as part of the oil and natural gas property balance. The following table is a reconciliation of the ARO (in thousands): March 31, December 31, 2018 2017 Asset retirement obligation, beginning balance $ 6,074 $ 13,579 Liabilities added from escalating working interests 288 198 Sales — (8,416) Settlements — (60) Accretion expense 126 773 Asset retirement obligation, ending balance $ 6,488 $ 6,074 Additional AROs increase the liability associated with new oil and natural gas wells and other facilities as these obligations are incurred. Abandonments of oil and natural gas wells and other facilities reduce the liability for AROs. During the three months ended March 31, 2018, and the year ended December 31, 2017, there were no significant expenditures for abandonments and there were no assets legally restricted for purposes of settling existing AROs. During the year ended December 31, 2017, obligations were sold as part of the Oklahoma Production Divestiture and Texas Production Divestiture.

Intangible Assets

Intangible Assets	3 Months Ended
	Mar. 31, 2018
Intangible Assets
Intangible Assets	10. INTANGIBLE ASSETS Intangible assets are comprised of customer and marketing contracts. The intangible assets balance includes $168.8 million related to the Gathering Agreement (defined in Note 13 “Related Party Transactions”) with Sanchez Energy that was entered into as part of the acquisition of the Western Catarina gathering system (“Western Catarina Midstream”). Pursuant to the 15-year agreement, Sanchez Energy tenders all of its crude petroleum, natural gas and other hydrocarbon-based product volumes on 35,000 dedicated acres in the Western Catarina of the Eagle Ford Shale in Texas for processing and transportation through Western Catarina Midstream, with a right to tender additional volumes outside of the dedicated acreage. These intangible assets are being amortized using the straight-line method over the 15-year life of the agreement. Amortization expense for each of the three months ended March 31, 2018 and 2017 was $3.4 million. These costs are amortized to depreciation, depletion, and amortization expense in our condensed consolidated statement of operations. Intangible assets as of March 31, 2018, and December 31, 2017 are detailed below (in thousands): March 31, December 31, 2018 2017 Beginning balance $ 172,166 $ 185,766 Disposals — (32) Amortization (3,365) (13,568) Ending balance $ 168,801 $ 172,166

Investments

Investments	3 Months Ended
	Mar. 31, 2018
Investments
Investments	11. INVESTMENTS In July 2016, we completed a transaction pursuant to which we acquired from Sanchez Energy a 50% interest in Carnero Gathering, a joint venture that is 50% owned and operated by Targa for an initial payment of approximately $37.0 million and the assumption of remaining capital commitments to Carnero Gathering, estimated at approximately $7.4 million as of the acquisition date (the “Carnero Gathering Transaction”). During the three months ended March 31, 2018, the Partnership made approximately $0.1 million of capital contributions to Carnero Gathering. Prior to the sale, Sanchez Energy, through a wholly owned subsidiary, had invested approximately $26.0 million in Carnero Gathering. The fair value of the intangible asset for the contractual customer relationship related to Carnero Gathering was valued at approximately $13.0 million. This amount is being amortized over a contract term of fifteen years and decreases earnings from Carnero Gathering. As part of the Carnero Gathering Transaction, we are required to pay Sanchez Energy an earnout based on natural gas received above a threshold volume and tariff at Carnero Gathering’s delivery points from Sanchez Energy and other producers. See Note 5 “Fair Value Measurements” for further discussion of the earnout derivative. As of March 31, 2018, the Partnership had paid approximately $46.4 million for the Carnero Gathering Transaction related to the initial payment and contributed capital. The Partnership has accounted for this investment using the equity method. Targa is the operator of the joint venture and has significant influence with respect to the normal day-to-day construction and operating decisions. We have included the investment balance in the “Equity investments” caption in our condensed consolidated balance sheet. For the three months ended March 31, 2018, the Partnership recorded earnings of approximately $2.2 million in equity investments from Carnero Gathering, which was offset by approximately $0.2 million related to the amortization of the contractual customer intangible asset. We have included these equity method earnings in the “Earnings from equity investments” line within the condensed consolidated statements of operations. Cash distributions of approximately $2.6 million were received during the three months ended March 31, 2018. In November 2016, we completed a transaction pursuant to which we acquired from Sanchez Energy a 50% interest in Carnero Processing, LLC, a joint venture that is 50% owned and operated by Targa, for aggregate cash consideration of approximately $55.5 million and the assumption of remaining capital contribution commitments to Carnero Processing, estimated at approximately $24.5 million as of the date of acquisition (the “Carnero Processing Transaction”). During the three months ended March 31, 2018, the Partnership made approximately $0.2 million of capital contributions to the joint venture. Prior to the sale, Sanchez Energy, through a wholly owned subsidiary, had invested approximately $48.0 million in Carnero Processing. As of March 31, 2018, the Partnership had paid approximately $74.9 million for the Carnero Processing Transaction related to the initial payment, acquisition costs and contributed capital. The Partnership has accounted for this investment using the equity method. Targa is the operator of the joint venture and has significant influence with respect to the normal day-to-day operating decisions. We have included the investment balance in the “Equity investments” caption in our consolidated balance sheet. The Partnership recorded earnings of approximately $2.3 million in the “Earnings from equity investments” line within our consolidated statements of operations for the three months ended March 31, 2018. Cash distributions of approximately $4.4 million were received during the three months ended March 31, 2018. Summarized financial information of unconsolidated entities is as follows (in thousands): Three Months Ended March 31, 2018 2017 Sales $ 89,789 $ 3,071 Total expenses 80,662 1,373 Net income $ 9,127 $ 1,698 March 31, December 31, 2018 2017 Current assets $ 35,888 $ 38,344 Noncurrent assets 192,765 193,748 Current liabilities 25,601 24,710

Commitments And Contingencies

Commitments And Contingencies	3 Months Ended
	Mar. 31, 2018
Commitments And Contingencies
Commitments And Contingencies	12. COMMITMENTS AND CONTINGENCIES As part of the Carnero Gathering Transaction, we are required to pay Sanchez Energy an earnout based on natural gas received above a threshold volume and tariff at Carnero Gathering’s delivery points from Sanchez Energy and other producers. This earnout has an approximate value of $6.7 million and was recorded on the balance sheet as a deferred liability as of March 31, 2018. We did not have any other material commitments and contingencies and no earnout payments were made during the three months ended March 31, 2018.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2018
Related Party Transactions
Related Party Transactions	13. RELATED PARTY TRANSACTIONS Sanchez-Related Agreements We are controlled by our general partner. The sole member of our general partner is Manager, which has no officers. In May 2014, we entered into the Services Agreement with Manager pursuant to which Manager provides services that we require to operate our business, including overhead, technical, administrative, marketing, accounting, operational, information systems, financial, compliance, insurance, acquisition, disposition and financing services and professionals. In connection with providing services under the Services Agreement, Manager receives compensation consisting of: (i) a quarterly fee equal to 0.375% of the value of our properties other than our assets located in the Mid-Continent region, (ii) reimbursement for all allocated overhead costs as well as any direct third-party costs incurred and (iii) for each asset acquisition, asset disposition and financing, a fee not to exceed 2% of the value of such transaction. Each of these fees, not including the reimbursement of costs, is paid in cash unless Manager elects for such fee to be paid in our equity. The Services Agreement has a ten-year term and will be automatically renewed for additional ten years unless either Manager or the Partnership provides notice of termination to the other with at least 180 days’ notice. During the three months ended March 31, 2018, we incurred costs of approximately $2.3 million to Manager under the Services Agreement. Manager utilizes SOG to provide the services under the Services Agreement. In May 2014, we entered into a Contract Operating Agreement with SOG pursuant to which SOG either provides services to operate, develop and produce our oil and natural gas properties or engages a third-party operator to do so, other than with respect to our properties in the Mid-Continent Region. We also have entered into the Geophysical Seismic Data Use License Agreement with SOG pursuant to which SOG provides us a non-exclusive, royalty-free license to use seismic, geophysical and geological information relating to our oil and natural gas properties that is proprietary to SOG and not restricted by agreements that SOG has with landowners or seismic data vendors. SOG, headquartered in Houston, Texas, is a private full-service oil and natural gas company engaged in the exploration and development of oil and natural gas primarily in the South Texas and onshore Gulf Coast areas on behalf of its affiliates. The Chairman of the board of directors of our general partner, Antonio R. Sanchez III, the President and Chief Operating Officer of our general partner as well as one of our directors, Patricio D. Sanchez, one of our directors, Eduardo A. Sanchez, along with their immediate family members, Ana Lee Sanchez Jacobs and Antonio R. Sanchez, Jr., collectively, either directly or indirectly, own a majority of the equity interests of SOG. In addition, Antonio R. Sanchez, Jr. is a member of the board of directors of SOG, and such other individuals, as well as Ana Lee Sanchez Jacobs, are officers of SOG. Sanchez-Related Transactions We have entered into several transactions with Sanchez Energy since January 1, 2016. Antonio R. Sanchez, Jr. is a director and Executive Chairman of the Board of Sanchez Energy, and Antonio R. Sanchez, III is a director and Chief Executive Officer of Sanchez Energy. In addition, Eduardo A. Sanchez is the former President of Sanchez Energy and Patricio D. Sanchez is an Executive Vice President of Sanchez Energy. The employees of SOG, including Kirsten A. Hink, our Chief Accounting Officer, provide common services to both us and Sanchez Energy. In conjunction with the acquisition of Western Catarina Midstream, we entered into a 15-year gas gathering agreement with Sanchez Energy pursuant to which Sanchez Energy agreed to tender all of its crude petroleum, natural gas and other hydrocarbon-based product volumes on approximately 35,000 dedicated acres in the Western Catarina area of the Eagle Ford Shale in Texas for processing and transportation through Western Catarina Midstream, with the potential to tender additional volumes outside of the dedicated acreage (the “Gathering Agreement”). During the first five years of the term of the Gathering Agreement, Sanchez Energy is required to meet a minimum quarterly volume delivery commitment of 10,200 barrels per day of oil and condensate and 142,000 Mcf per day of natural gas, subject to certain adjustments. Sanchez Energy is required to pay gathering and processing fees of $0.96 per barrel for crude oil and condensate and $0.74 per Mcf for natural gas that are tendered through Western Catarina Midstream, in each case, subject to an annual escalation for a positive increase in the consumer price index. For the three months ended March 31, 2018 and 2017, Sanchez Energy paid us approximately $14.0 million and $12.6 million, respectively, pursuant to the terms of the Gathering Agreement. Under Topic 606, this amount is being presented under gathering and transportation lease revenue on the condensed consolidated statements of operations. On June 30, 2017, the Gathering Agreement was amended to add an incremental infrastructure fee to be paid by a subsidiary of Sanchez Energy based on water that is delivered through the gathering system through March 31, 2018. As part of the Carnero Gathering Transaction, we are required to pay Sanchez Energy an earnout based on natural gas received above a threshold volume and tariff at Carnero Gathering’s delivery points from Sanchez Energy and other producers. For the three months ended March 31, 2018 and 2017, natural gas received did not exceed the threshold. However, we made an earnout payment to Sanchez Energy for $0.1 million in the first quarter of 2018 related to the year ended December 31, 2017. The earnout is being accounted for as a derivative in the condensed consolidated financial statements. Refer to Note 5 “Fair Value Measurements” for additional discussion. In November 2016, in conjunction with our public offering of common units, the Partnership entered into a Common Unit Purchase Agreement with SN UR Holdings, LLC (the “Purchaser”), a wholly owned subsidiary of Sanchez Energy, whereby we issued to the Purchaser 2,272,727 common units for proceeds of approximately $25.0 million. In November 2016, we completed the Carnero Processing Transaction pursuant to which we acquired from Sanchez Energy a 50% interest in Carnero Processing, a joint venture that is 50% owned and operated by Targa, for aggregate cash consideration of approximately $55.5 million and the assumption of remaining capital contribution commitments to Carnero Processing, estimated at approximately $24.5 million as of the date of acquisition. Also in November 2016, the Partnership consummated a Purchase and Sale Agreement with SN Cotulla Assets, LLC and SN Palmetto, LLC, each a wholly-owned subsidiary of Sanchez Energy, to purchase working interests in 23 producing Eagle Ford Shale wellbores located in Dimmit and Zavala counties in South Texas as well as escalating working interests in an additional 11 producing wellbores in the Palmetto Field in Gonzales, Texas for approximately $24.2 million. In October 2016, we entered into an agreement with Sanchez Energy providing us an option to acquire a ground lease, which the parties mutually terminated in September 2017. In September 2017, we entered into an agreement with a subsidiary of Sanchez Energy to transport certain quantities of the subsidiary’s natural gas on a firm basis through the Seco Pipeline, a 100% owned and operated 30 mile natural gas pipeline with 400 MMcf/d capacity that is designed and used to transport dry gas from the Raptor Gas Processing Facility to multiple markets in South Texas (the “Seco Pipeline”), for $0.22 per MMBtu delivered on or after September 1, 2017 (the “Seco Pipeline Transportation Agreement”). The Seco Pipeline Transportation Agreement continues month-to-month until terminated by either party. For the three months ended March 31, 2018, SN Catarina paid us approximately $0.5 million pursuant to the terms of that agreement. As of March 31, 2018 and December 31, 2017, the Partnership had a net receivable from related parties of approximately $6.1 million, and $13.1 million, respectively, which are included in “Accounts receivable – related entities” in the consolidated balance sheets. As of March 31, 2018 and December 31, 2017, the Partnership also had a net payable to related parties of approximately $6.9 million, and $10.4 million, respectively. The net receivable/payable as of March 31, 2018 and December 31, 2017 consist primarily of revenues receivable from oil and natural gas production and transportation, offset by costs associated with that production and transportation and obligations for general and administrative costs. Sanchez Energy is an independent exploration and production company focused on the acquisition and development of U.S. onshore unconventional oil and natural gas resources, with a current focus on the horizontal development of significant resource potential from the Eagle Ford Shale in South Texas where it has assembled approximately 487,000 gross leasehold acres (285,000 net acres). The Chairman of the board of directors of our general partner, Antonio R. Sanchez, III, is Sanchez Energy’s Chief Executive Officer and a member of its board of directors. A member of the board of directors of our general partner, Eduardo A. Sanchez, is the former President of Sanchez Energy. The President and Chief Operating Officer of our general partner, Patricio D. Sanchez, who is also a member of the board of directors of our general partner, is an Executive Vice President of Sanchez Energy. Antonio R. Sanchez, Jr., the father of Antonio R. Sanchez, III, Eduardo A. Sanchez, and Patricio D. Sanchez, is the Executive Chairman of the board of directors of Sanchez Energy. Antonio R. Sanchez, Jr., Antonio R. Sanchez, III, and Patricio D. Sanchez beneficially own approximately 6.8%, 3.0%, and 1.2%, respectively, of Sanchez Energy’s shares outstanding as of March 31, 2018. Sanchez Energy indirectly, through one of its wholly owned subsidiaries, beneficially owned approximately 15.0% of the outstanding common units of SNMP as of March 31, 2018.

Unit-Based Compensation

Unit-Based Compensation	3 Months Ended
	Mar. 31, 2018
Unit-Based Compensation
Unit-Based Compensation	14. UNIT-BASED COMPENSATION The Sanchez Midstream Partners LP Long-Term Incentive Plan (the “LTIP”) allows for restricted common unit grants. Restricted common unit activity under the LTIP during the period is presented in the following table: Weighted Average Number of Grant Date Restricted Fair Value Units Per Unit Outstanding at December 31, 2017 283,138 $ 14.64 Granted — — Vested (171,231) 14.60 Returned/Cancelled (4,166) 13.59 Outstanding at March 31, 2018 107,741 $ 14.73 In March 2017, the Partnership issued 171,231 restricted common units pursuant to the LTIP to executives of the Partnership’s general partner that vest on the first anniversary of grant. The unit-based compensation expense for the award was based on the fair value on the day before the date of grant. As of March 31, 2018, 1,634,947 common units remained available for future issuance to participants under the LTIP.

Distributions To Unitholders

Distributions To Unitholders	3 Months Ended
	Mar. 31, 2018
Distributions To Unitholders
Distributions To Unitholders	15. DISTRIBUTIONS TO UNITHOLDERS The table below reflects the payment of cash distributions on common units related to the three months ended March 31, 2018 and the year ended December 31, 2017. Distribution Date of Date of Date of Three months ended per unit declaration record distribution March 31, 2017 $ 0.4375 May 10, 2017 May 22, 2017 May 31, 2017 June 30, 2017 $ 0.4441 August 9, 2017 August 22, 2017 August 31, 2017 September 30, 2017 $ 0.4508 November 7, 2017 November 20, 2017 November 30, 2017 December 31, 2017 $ 0.4508 February 8, 2018 February 20, 2018 February 28, 2018 March 31, 2018 $ 0.4508 May 8, 2018 May 22, 2018 May 31, 2018 The table below reflects the payment of distributions on Class B preferred units related to the three months ended March 31, 2018, and the year ended December 31, 2017. Cash distribution Date of Date of Date of Three months ended per unit declaration record distribution March 31, 2017 (a) $ 0.2258 May 10, 2017 May 22, 2017 May 31, 2017 June 30, 2017 $ 0.28225 August 9, 2017 August 22, 2017 August 31, 2017 September 30, 2017 $ 0.28225 November 7, 2017 November 20, 2017 November 30, 2017 December 31, 2017 $ 0.28225 February 8, 2018 February 20, 2018 February 28, 2018 March 31, 2018 $ 0.28225 May 8, 2018 May 22, 2018 May 31, 2018 (a) The Partnership elected to pay the first quarter 2017 distribution on the Class B preferred units in part cash and, with the consent of the Class B preferred unitholder, in part common units (in lieu of additional Class B preferred units). Accordingly, the Partnership declared a cash distribution of $0.2258 per Class B preferred unit and an aggregate distribution of 184,697 common units, each payable on May 31, 2017 to holders of record on May 22, 2017.

Partners' Capital

Partners' Capital	3 Months Ended
	Mar. 31, 2018
Partners' Capital
Partners' Capital	16. PARTNERS’ CAPITAL Outstanding Units As of March 31, 2018, we had 31,000,887 Class B Preferred Units outstanding, and 15,171,946 common units outstanding, which included 107,741 unvested restricted common units issued under the LTIP. Common Unit Issuances In connection with providing services under the Services Agreement for the fourth quarter of 2017, the Partnership issued 210,978 common units to SP Holdings, LLC on March 15, 2018. In connection with providing services under the Services Agreement for the first, second and third quarters of 2017, the Partnership issued 139,110, 170,497 and 186,942 common units, respectively, to SP Holdings, LLC on June 30, 2017, August 31, 2017 and November 30, 2017, respectively. In connection with providing services under the Services Agreement for the third and fourth quarters of 2016, the Partnership issued 170,750 and 154,737 common units, respectively, to SP Holdings, LLC on March 6, 2017. See Note 13, “Related Party Transactions” for additional information related to the Services Agreement. The Partnership elected to pay the first quarter 2017 distribution on the Class B preferred units in part cash and, with the consent of the Class B preferred unitholder, in part common units (in lieu of additional Class B preferred units). Accordingly, the Partnership issued 184,697 common units on May 22, 2017, to the holder of Class B preferred units. In April 2017, we issued 84,577 common units in registered offerings for gross proceeds of approximately $1.3 million pursuant to a shelf registration statement originally filed with the SEC on March 6, 2015 as updated by that certain prospectus supplement filed with the SEC on April 6, 2017 (the “Shelf Registration Statement”). The Shelf Registration Statement allows the Partnership to sell up to $50.0 million of common units at-the-market to fund general limited partnership purposes, including possible acquisitions. Proceeds from the at-the-market equity issuance were used for general limited partnership purposes. Class B Preferred Unit Offering On October 14, 2015, pursuant to that certain Class B Preferred Unit Purchase Agreement dated September 25, 2015 between the Partnership and Stonepeak Catarina Holdings LLC (“Stonepeak”), the Partnership sold and Stonepeak purchased 19,444,445 of the Partnership’s newly created Class B Preferred Units (the “Class B Preferred Units”) in a privately negotiated transaction for an aggregate cash purchase price of $18.00 per Class B Preferred Unit, which resulted in gross proceeds to the Partnership of approximately $350.0 million. The Partnership used the net proceeds to pay a portion of the consideration for the acquisition of Western Catarina Midstream, along with the payment to Stonepeak of a fee equal to 2.25% of the consideration paid for the Class B Preferred Units. Under the terms of our partnership agreement, holders of the Class B Preferred Units received a quarterly distribution, at the election of the board of directors of our general partner, of 10.0% per annum if paid in full in cash or 12.0% per annum if paid in part cash (8.0% per annum) and in part paid-in-kind units (4.0% per annum). Distributions are to be paid on or about the last day of each of February, May, August and November after the end of each quarter. In accordance with the partnership agreement, on December 6, 2016 we issued an additional 9,851,996 Class B preferred units to Stonepeak. On January 25, 2017, the Partnership and Stonepeak entered into a Settlement Agreement and Mutual Release (the “Settlement Agreement”) to settle a dispute arising from the calculation of an adjustment to the number of Class B Preferred Units pursuant to Section 5.10(g) of the Second Amended and Restated Agreement of Limited Partnership of the Partnership (the “Amended Partnership Agreement”). Pursuant to the Settlement Agreement, and in accordance with Section 5.4 of the Amended Partnership Agreement, the Partnership issued 1,704,446 Class B Preferred Units to Stonepeak in a privately negotiated transaction as partial consideration for the Settlement Agreement, with the “Class B Preferred Unit Price” being established at $11.29 per Class B Preferred Unit. Pursuant to the terms of the Amended Partnership Agreement, the Class B Preferred Units are convertible at any time, at the option of Stonepeak, into common units of the Partnership, subject to the requirement to convert a minimum of $17.5 million of Class B Preferred Units. The issuance of the Class B Preferred Units pursuant to the Settlement Agreement was made in reliance upon an exemption from the registration requirements of the Securities Act of 1933 pursuant to Section 4(a)(2) thereof. The Class B Preferred Units are accounted for as mezzanine equity in the consolidated balance sheet consisting of the following (in thousands): March 31, December 31, 2018 2017 Mezzanine equity beginning balance $ 343,912 $ 342,991 Amortization of discount 531 1,796 Distributions 8,750 35,875 Distributions paid (8,750) (36,750) Total mezzanine equity $ 344,443 $ 343,912 Earnings per Unit Net income (loss) per common unit for the period is based on any distributions that are made to the unitholders (common units) plus an allocation of undistributed net income (loss) based on provisions of the partnership agreement, divided by the weighted average number of common units outstanding. The two-class method dictates that net income (loss) for a period be reduced by the amount of distributions and that any residual amount representing undistributed net income (loss) be allocated to common unitholders and other participating unitholders to the extent that each unit may share in net income (loss) as if all of the net income for the period had been distributed in accordance with the partnership agreement. Unit-based awards granted but unvested are eligible to receive distributions. The underlying unvested restricted unit awards are considered participating securities for purposes of determining net income (loss) per unit. Undistributed income (loss) is allocated to participating securities based on the proportional relationship of the weighted average number of common units and unit-based awards outstanding. Undistributed losses (including those resulting from distributions in excess of net income) are allocated to common units based on provisions of the partnership agreement. Undistributed losses are not allocated to unvested restricted unit awards as they do not participate in net losses. Distributions declared and paid in the period are treated as distributed earnings in the computation of earnings per common unit even though cash distributions are not necessarily derived from current or prior period earnings. Our general partner does not have an economic interest in the Partnership and, therefore, does not participate in the Partnership’s net income.

Reporting Segments

Reporting Segments	3 Months Ended
	Mar. 31, 2018
Reporting Segments
Reporting Segments	17. REPORTING SEGMENTS “Midstream” and “Production” best describe the operating segments of the businesses that we separately report. The factors used to identify these reporting segments are based on the nature of the operations that are undertaken by each segment. The Midstream segment operates the gathering, processing and transportation of crude oil, natural gas and NGLs. The Production segment operates to produce crude oil and natural gas. These segments are broadly understood across the petroleum and petrochemical industries. These functions have been defined as the operating segments of the Partnership because they are the segments (1) that engage in business activities from which revenues are earned and expenses are incurred; (2) whose operating results are regularly reviewed by the Partnership’s chief operating decision maker (“CODM”) to make decisions about resources to be allocated to the segment and to assess its performance; and (3) for which discrete financial information is available. Operating segments are evaluated for their contribution to the Partnership’s consolidated results based on operating income, which is defined as segment operating revenues less expenses. We realigned the composition of our operating segments to reflect management's view of the operating results during the fourth quarter 2017. The following tables present financial information for each operating segment for the periods indicated based on the realignment of our operating segments (in thousands): Three Months Ended March 31, 2018 Production Midstream Total Segment revenues Natural gas sales $ 473 $ — $ 473 Oil sales 3,462 — 3,462 Natural gas liquid sales 595 — 595 Gathering and transportation sales — 1,688 1,688 Gathering and transportation lease revenues — 12,318 12,318 Total segment revenues 4,530 14,006 18,536 Segment operating costs Lease operating expenses 1,752 219 1,971 Transportation operating expenses — 2,847 2,847 Production taxes 322 — 322 Depreciation, depletion and amortization 1,363 5,265 6,628 Accretion expense 54 72 126 Total segment operating costs 3,491 8,403 11,894 Segment other income Earnings from equity investments — 4,272 4,272 Total segment other income — 4,272 4,272 Segment operating income $ 1,039 $ 9,875 $ 10,914 Three Months Ended March 31, 2017 Production Midstream Total Segment operating revenues Natural gas sales $ 2,779 $ — $ 2,779 Oil sales 11,350 — 11,350 Natural gas liquid sales 467 — 467 Gathering and transportation sales — 11,211 11,211 Total segment operating revenues 14,596 11,211 25,807 Segment operating costs Lease operating expenses 4,724 259 4,983 Transportation operating expenses — 3,296 3,296 Cost of sales 37 — 37 Production taxes 473 — 473 Depreciation, depletion and amortization 3,281 8,900 12,181 Asset impairments 4,688 — 4,688 Accretion expense 192 66 258 Total segment operating costs 13,395 12,521 25,916 Segment other income Earnings from equity investments (136) 618 482 Total segment other income (loss) (136) 618 482 Segment operating income (loss) $ 1,065 $ (692) $ 373 Three Months Ended March 31, 2018 2017 Reconciliation of segment operating income to net income (loss) Total segment operating income $ 10,914 $ 373 General and administrative (5,165) (5,609) Unit-based compensation expense (1,438) (540) Interest expense, net (2,599) (1,883) Other income (expense) (a) (270) — Net income (loss) $ 1,442 $ (7,659) (a) Other expense in 2017 excludes earnout rebate. As the rebate is reviewed by the CODM at the segment level, it was included in the Midstream segment operating costs. The following table summarizes the total assets and capital expenditures by operating segment based on the segment realignment as of March 31, 2018 and 2017 (in thousands): March 31, 2018 Production Midstream Corporate (a) Total Other financial information Total assets $ 54,799 $ 455,388 $ 2,775 $ 512,962 Capital expenditures (b) $ 3 $ 701 $ — $ 704 December 31, 2017 Production Midstream Corporate (a) Total Other financial information Total assets $ 58,623 $ 468,656 $ 1,144 $ 528,423 Capital expenditures (b) $ 441 $ 46,452 $ — $ 46,893 (a) Corporate assets not reviewed by the CODM on a segment basis consists of cash, certain prepaids, office furniture, and other assets. (b) Inclusive of capital contributions made to equity method investments.

Variable Interest Entities

Variable Interest Entities	3 Months Ended
	Mar. 31, 2018
Variable Interest Entities
Variable Interest Entities	18. VARIABLE INTEREST ENTITIES During the year ended December 31, 2016, the Partnership adopted ASU 2015-02, “Consolidation—Amendments to the Consolidation Analysis,” which introduces a separate analysis for determining if limited partnerships and similar entities are variable interest entities (“VIEs”) and clarifies the steps a reporting entity would have to take to determine whether the voting rights of stockholders in a corporation or similar entity are substantive. As noted above in Note 11, “Investments,” the Partnership acquired a 50% membership interest in Carnero Gathering from a subsidiary of Sanchez Energy for an initial payment of approximately $37.0 million and the assumption of remaining capital commitments to Carnero Gathering, estimated at approximately $7.4 million as of the date of the acquisition. The Partnership determined that the Carnero Gathering joint venture is more similar to a limited partnership than a corporation. Under the revised guidance of ASU 2015-02, a limited partnership or similar entity with equity at risk will not be a variable interest entity (“VIE”) if a partner is able to exercise kick-out rights over the general partner(s) or is able to exercise substantive participating rights. We concluded that the Carnero Gathering joint venture is a VIE under the revised guidance because we cannot remove Targa as operator and we do not have substantive participating rights. In addition, Targa has the discretion to direct activities of the VIE regarding the risks associated with price, operations, and capital investment which have the most significant impact on the VIE’s economic performance. The Partnership’s investment in Carnero Gathering represents a VIE that could expose the Partnership to losses. The amount of losses the Partnership could be exposed to from the Carnero Gathering joint venture is limited to the capital investment of approximately $47.4 million. As of March 31, 2018, the Partnership had invested approximately $46.4 million in Carnero Gathering. As of March 31, 2018, no debt has been incurred by Carnero Gathering. We have included this VIE in the “Equity investments” long-term asset line on the balance sheet. As noted above in Note 11, “Investments,” the Partnership acquired a 50% membership interest in Carnero Processing from a subsidiary of Sanchez Energy for an initial payment of approximately $55.5 million and the assumption of remaining capital commitments to Carnero Processing, estimated at approximately $24.5 million as of the date of the acquisition. The Partnership determined that the Carnero Processing joint venture is more similar to a limited partnership than a corporation. Under the revised guidance of ASU 2015-02, a limited partnership or similar entity with equity at risk will not be a VIE if a limited partner is able to exercise kick-out rights over the general partner(s) or is able to exercise substantive participating rights. We concluded that the Carnero Processing joint venture is a VIE under the revised guidance because we cannot remove Targa as operator and we do not have substantive participating rights. In addition, Targa has the discretion to direct activities of the VIE regarding the risks associated with price, operations, and capital investment which have the most significant impact on the VIE’s economic performance. Similar to the Partnership’s investment in Carnero Gathering, the Partnership’s investment in Carnero Processing represents a VIE that could expose the Partnership to losses. The amount of losses the Partnership could be exposed to from the Carnero Processing joint venture is limited to the capital investment of approximately $73.9 million. As of March 31, 2018, the Partnership had invested approximately $74.9 million in Carnero Processing. As of March 31, 2018, no debt has been incurred by Carnero Processing. We have included this VIE in the “Equity investments” long-term asset line on the balance sheet. Below is a tabular comparison of the carrying amounts of the assets and liabilities of the VIE and the Partnership’s maximum exposure to loss as of March 31, 2018 and December 31, 2017 (in thousands): March 31, December 31, 2018 2017 Acquisitions and capital investments $ 125,323 $ 125,059 Earnings in equity investments 14,559 10,288 Distributions received (18,624) (11,632) Maximum exposure to loss $ 121,258 $ 123,715

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2018
Subsequent Events
Subsequent Events	19. SUBSEQUENT EVENTS On May 8, 2018, the board of directors of our general partner declared a first quarter 2018 cash distribution on the Partnership’s common units of $0.4508 per unit ($1.8032 per unit annualized) payable on May 31, 2018 to holders of record on May 22, 2018. The Partnership also declared a first quarter distribution on the Class B preferred units and elected to pay the distribution in cash. Accordingly, the Partnership declared a cash distribution of $0.28225 per Class B preferred unit payable on May 31, 2018 to holders of record on May 22, 2018. On April 30, 2018, a subsidiary of the Partnership, SEP Holdings IV, LLC (“SEP”) entered into an Agreement to Purchase Oil and Gas Interests with EP Energy E&P Company, L.P. (“EP”), pursuant to which EP bought specified wellbores and other associated assets and interests in La Salle County Texas from SEP (the “Briggs Assets”) for a base purchase price of approximately $4.5 million, which after giving effect to preliminary purchase price adjustments was reduced to approximately $4.0 million (the “Briggs Divestiture”), which remains subject to customary post-closing adjustments. In addition, other than a limited amount of retained obligations, EP agreed to assume all obligations relating to the Briggs Assets, including all plugging and abandonment costs, that arose on or after March 1, 2018.

Basis Of Presentation And Sum27

Basis Of Presentation And Summary Of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2018
Basis Of Presentation And Summary Of Significant Accounting Policies
Basis of Presentation	Basis of Presentation Accounting policies used by us conform to accounting principles generally accepted in the United States of America (“U.S. GAAP”). These unaudited condensed consolidated financial statements include the accounts of us and our wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. We conduct our business activities as two operating segments: the production of oil and natural gas and the midstream business, which includes Western Catarina Midstream (defined in Note 10). Our management evaluates performance based on these two business segments. These unaudited condensed consolidated financial statements have been prepared pursuant to the rules of the SEC. Certain information and footnote disclosures, normally included in annual financial statements prepared in accordance with U.S. GAAP, have been condensed or omitted pursuant to those rules and regulations. We believe that the disclosures made are adequate to make the information presented not misleading. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, necessary to fairly state the financial position, results of operations and cash flows with respect to the interim condensed consolidated financial statements have been included. The results of operations for the interim periods are not necessarily indicative of the results for the entire year. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto of SNMP and its subsidiaries included in our Annual Report on Form 10-K for the year ended December 31, 2017, which was filed with the SEC on March 12, 2018.
Recent Accounting Pronouncements	Recent Accounting Pronouncements From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”), which are adopted by us as of the specified effective date. Unless otherwise discussed, management believes that the impact of recently issued standards, which are not effective, will not have a material impact on our condensed consolidated financial statements upon adoption. In January 2017, the FASB issued Accounting Standards Update (“ASU”) 2017-01 “Business Combinations (Topic 805) - Clarifying the Definition of a Business,” which provides a new framework for determining whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. This ASU is effective for public business entities for annual and interim periods in fiscal years beginning after December 15, 2017. The Partnership adopted this ASU on January 1, 2018, using a prospective method; the clarified definition of a business will be applied by the Partnership to transactions executed subsequent to the effective date. In November 2016, the FASB issued ASU 2016-18 “Statement of Cash Flows (Topic 230): Restricted Cash,” which requires companies to include cash and cash equivalents that have restrictions on withdrawal or use in total cash and cash equivalents on the statement of cash flows. This ASU is now effective for public business entities beginning after December 15, 2017. The Partnership does not currently have restricted cash. In October 2016, the FASB issued ASU 2016-16 “Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory,” which eliminates a current exception in U.S. GAAP to the recognition of the income tax effects of temporary differences that result from intra-entity transfers of non-inventory assets. The intra-entity exception is being eliminated under the ASU. The standard is required to be applied on a modified retrospective basis and is now effective for public business entities for annual and interim periods in fiscal years beginning after December 15, 2017. The adoption of ASU 2016-16 did not have an impact on the Partnership’s unaudited condensed consolidated financial statements and related disclosures. In February 2016, the FASB issued ASU No. 2016-02 “Leases (Topic 842),” effective for annual and interim periods for public companies beginning after December 15, 2018, with a modified retrospective approach to be used for implementation. ASU 2016-02 updates the previous lease guidance by requiring the recognition of a right-to-use asset and lease liability on the statement of financial position for those leases previously classified as operating leases under the old guidance. In addition, ASU 2016-02 updates the criteria for a lessee’s classification of a finance lease. The Partnership will not early adopt this standard and will apply the revised lease rules for our interim and annual reporting periods starting January 1, 2019. The Partnership is currently evaluating the impact of these rules on its consolidated financial statements and has started the assessment process by evaluating the population of leases under the revised definition. The Partnership is also in the process of implementing a lease accounting software to properly account for lease data upon adoption. The adoption of this standard will result in an increase in the assets and liabilities on the Partnership’s consolidated balance sheets. The quantitative impacts of the new standard are dependent on the leases in force at the time of adoption. As a result, the evaluation of the effect of the new standards will extend over future periods. In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606).” In March, April, May and December of 2016, the FASB issued rules clarifying several aspects of the new revenue recognition standard. The new guidance is effective for fiscal years and interim periods beginning after December 15, 2017. This guidance outlines a new, single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. This new revenue recognition model provides a five-step analysis in determining when and how revenue is recognized. The new model will require revenue recognition to depict the transfer of promised goods or services to customers in an amount that reflects the consideration a company expects to receive in exchange for those goods and services. The new standard also requires more detailed disclosures related to the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. The Partnership adopted the standard effective January 1, 2018. For more information, see Note 3 “Revenue Recognition.” Other accounting standards that have been issued by the FASB or other standards-setting bodies are not expected to have a material impact on the Partnership’s financial position, results of operations and cash flows.
Estimates	Estimates The condensed consolidated financial statements are prepared in conformity with U.S. GAAP, which requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying footnotes. These estimates and the underlying assumptions affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities and reported amounts of revenues and expenses. The estimates that are particularly significant to our financial statements include estimates of our reserves of natural gas, NGLs and oil; future cash flows from oil and natural gas properties; depreciation, depletion and amortization; asset retirement obligations; certain revenues and operating expenses; fair values of derivatives; and fair values of assets and liabilities. As fair value is a market-based measurement, it is determined based on the assumptions that market participants would use. These estimates and assumptions are based on management’s best judgment using the data available. Management evaluates its estimates and assumptions on an on-going basis using historical experience and other factors, including the current economic environment, which management believes to be reasonable under the circumstances. Such estimates and assumptions are adjusted when facts and circumstances dictate. As future events and their effects cannot be determined with precision, actual results could differ from the estimates. Any changes in estimates resulting from continuing changes in the economic environment will be reflected in the financial statements in future periods.

Revenue Recognition (Tables)

Revenue Recognition (Tables)	3 Months Ended
	Mar. 31, 2018
Schedule of disaggregation of revenue	The following table displays revenue disaggregated by type of revenue and product type (in thousands): For the Three Months Ended March 31, 2018 Production Midstream Total Revenues: Natural gas sales $ 473 $ — $ 473 Oil sales 3,462 — 3,462 Natural gas liquid sales 595 — 595 Gathering and transportation sales — 1,688 1,688 Gathering and transportation lease revenues — 12,318 12,318 Total revenues $ 4,530 $ 14,006 $ 18,536
Accounting Standards Update 2014-09
Schedule of cumulative effect of adoption of ASC 606	In accordance with the new revenue standard requirements, the disclosure of the impact of adoption on our condensed consolidated statement of operations is as follows (in thousands): For the Three Months Ended March 31, 2018 As reported Balances without Adoption Topic 606 Effect of change Higher/(Lower) Statement of Operations Gathering and transportation sales $ 1,688 $ 14,006 $ (12,318) Gathering and transportation lease revenues 12,318 — 12,318 Net earnings $ 14,006 $ 14,006 $ —

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2018
Fair Value Measurements
Fair Value Of Assets And Liabilities On A Recurring Basis	The following table summarizes the fair value of our assets and liabilities that were accounted for at fair value on a recurring basis as of March 31, 2018 (in thousands): Fair Value Measurements at March 31, 2018 Active Markets for Observable Identical Assets Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Fair Value Commodity derivative instrument Derivative liability $ — $ (477) $ — $ (477) Midstream derivative instrument Earnout derivative liability — — (6,672) (6,672) Total $ — $ (477) $ (6,672) $ (7,149) The following table summarizes the fair value of our assets and liabilities that were accounted for at fair value on a recurring basis as of December 31, 2017 (in thousands): Fair Value Measurements at December 31, 2017 Active Markets for Observable Identical Assets Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Fair Value Commodity derivative instrument Derivative assets $ — $ 1,231 $ — $ 1,231 Midstream derivative instrument Earnout derivative liability — — (6,402) (6,402) Total $ — $ 1,231 $ (6,402) $ (5,171)
Non-Recurring Fair Value Measurements Of Assets And Liabilities	The following table summarizes the non-recurring fair value measurements of our assets as of March 31, 2018 (in thousands): Fair Value Measurements at March 31, 2018 Active Markets for Observable Identical Assets Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Impairment $ — $ — $ — Total net assets $ — $ — $ — The following table summarizes the non-recurring fair value measurements of our assets as of December 31, 2017 (in thousands): Fair Value Measurements at December 31, 2017 Active Markets for Observable Identical Assets Inputs Unobservable Inputs (Level 1) (Level 2) (Level 3) Impairment (a) $ — $ — $ 7,277 Total net assets $ — $ — $ 7,277 During the year ended December 31, 2017, we recorded a non-cash impairment charge of $4.7 million to impair our producing oil and natural gas properties acquired in the Production Acquisition (defined in Note 8 “Oil and Natural Gas Properties”). The carrying values of the impaired properties were reduced to a fair value of $7.3 million, estimated using inputs characteristic of a Level 3 fair value measurement.
Reconciliation Of Changes In Fair Value Of Derivatives Classified As Level 3	The following table sets forth a reconciliation of changes in the fair value of the Partnership's earnout derivative classified as Level 3 in the fair value hierarchy for the three months ended March 31, 2018 and year ended Dec ember 31 , 2017 (in thousands): Three Months Ended Year Ended March 31, 2018 December 31, 2017 Beginning balance $ (6,402) $ (4,270) Initial fair value of earnout derivative — 221 Loss on earnout derivative (270) (2,353) Ending balance $ (6,672) $ (6,402) Loss included in earnings related to derivatives still held as of March 31, 2018 and December 31, 2017, respectively $ (270) $ (2,353)

Derivative And Financial Inst30

Derivative And Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2018
Derivative And Financial Instruments
Summary Of Derivative Contracts In Place	Fixed Price Basis Swaps – West Texas Intermediate (WTI) Three Months Ended (volume in Bbls) March 31, June 30, September 30, December 31, Total Average Average Average Average Average Volume Price Volume Price Volume Price Volume Price Volume Price 2018 — $ — 66,432 $ 59.71 62,840 $ 59.78 59,704 $ 59.84 188,976 $ 59.77 2019 62,528 $ 60.41 59,552 $ 60.44 57,024 $ 60.48 54,824 $ 60.52 233,928 $ 60.46 2020 52,776 $ 53.50 50,960 $ 53.50 49,224 $ 53.50 47,624 $ 53.50 200,584 $ 53.50 623,488 Fixed Price Swaps—NYMEX (Henry Hub) Three Months Ended (volume in MMBtu) March 31, June 30, September 30, December 31, Total Average Average Average Average Average Volume Price Volume Price Volume Price Volume Price Volume Price 2018 — $ — 126,600 $ 3.00 121,600 $ 3.00 117,040 $ 3.00 365,240 $ 3.00 2019 119,832 $ 2.85 115,784 $ 2.85 112,032 $ 2.85 108,552 $ 2.85 456,200 $ 2.85 2020 105,104 $ 2.85 102,008 $ 2.85 99,136 $ 2.85 96,200 $ 2.85 402,448 $ 2.85 1,223,888
Reconciliation Of Changes In Fair Value Of Derivatives	The following table sets forth a reconciliation of the changes in fair value of the Partnership’s commodity derivatives for the three months ended March 31, 2018 and the year ended December 31, 2017 (in thousands): Three Months Ended Year Ended March 31, 2018 December 31, 2017 Beginning fair value of commodity derivatives $ 1,231 $ 6,436 Net gains (losses) on crude oil derivatives (1,939) 3,284 Net gains on natural gas derivatives 2 663 Net settlements paid (received) on derivative contracts: Oil 229 (6,422) Natural gas — (2,730) Ending fair value of commodity derivatives $ (477) $ 1,231
Schedule Of Effect Of Derivative Instruments On Consolidated Statements Of Operations	Three Months Ended Year Ended March 31, 2018 December 31, 2017 Beginning fair value of commodity derivatives $ 1,231 $ 6,436 Net gains (losses) on crude oil derivatives (1,939) 3,284 Net gains on natural gas derivatives 2 663 Net settlements paid (received) on derivative contracts: Oil 229 (6,422) Natural gas — (2,730) Ending fair value of commodity derivatives $ (477) $ 1,231 The effect of derivative instruments on our condensed consolidated statements of operations was as follows (in thousands): Location of Gain(Loss) Three Months Ended March 31, Derivative Type in Income 2018 2017 Commodity – Mark-to-Market Oil sales $ (1,939) $ 5,495 Commodity – Mark-to-Market Natural gas sales 2 560 $ (1,937) $ 6,055

Oil And Natural Gas Propertie31

Oil And Natural Gas Properties And Related Equipment (Tables)	3 Months Ended
	Mar. 31, 2018
Oil And Natural Gas Properties And Related Equipment.
Gathering and Transportation Assets	Gathering and transportation assets consisted of the following (in thousands): March 31, December 31, 2018 2017 Gathering and transportation assets Midstream assets $ 185,407 $ 184,969 Less: Accumulated depreciation and amortization (28,770) (26,870) Total gathering and transportation assets $ 156,637 $ 158,099
Oil and Natural Gas Properties	March 31, December 31, 2018 2017 Gathering and transportation assets Midstream assets $ 185,407 $ 184,969 Less: Accumulated depreciation and amortization (28,770) (26,870) Total gathering and transportation assets $ 156,637 $ 158,099 Oil and natural gas properties consisted of the following (in thousands): March 31, December 31, 2018 2017 Oil and natural gas properties and related equipment Proved property $ 171,041 $ 170,750 Less: Accumulated depreciation, depletion, amortization and impairments (117,055) (115,704) Oil and natural gas properties and equipment, net $ 53,986 $ 55,046
Depreciation, Depletion, Amortization and Impairments	Depreciation, depletion, amortization and impairments consisted of the following (in thousands): Three Months Ended March 31, 2018 2017 Depreciation, depletion and amortization of oil and natural gas-related assets $ 1,363 $ 3,234 Depreciation and amortization of gathering and transportation related assets 1,900 5,535 Amortization of intangible assets 3,365 3,412 Total Depreciation, depletion and amortization 6,628 12,181 Asset impairments — 4,688 Total $ 6,628 $ 16,869

Asset Retirement Obligation (Ta

Asset Retirement Obligation (Tables)	3 Months Ended
	Mar. 31, 2018
Asset Retirement Obligation
Reconciliation of Asset Retirement Obligation	The following table is a reconciliation of the ARO (in thousands): March 31, December 31, 2018 2017 Asset retirement obligation, beginning balance $ 6,074 $ 13,579 Liabilities added from escalating working interests 288 198 Sales — (8,416) Settlements — (60) Accretion expense 126 773 Asset retirement obligation, ending balance $ 6,488 $ 6,074

Intangible Assets (Tables)

Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2018
Intangible Assets
Schedule of Intangible assets	Intangible assets as of March 31, 2018, and December 31, 2017 are detailed below (in thousands): March 31, December 31, 2018 2017 Beginning balance $ 172,166 $ 185,766 Disposals — (32) Amortization (3,365) (13,568) Ending balance $ 168,801 $ 172,166

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2018
Investments
Summarized financial information of unconsolidated entities	Summarized financial information of unconsolidated entities is as follows (in thousands): Three Months Ended March 31, 2018 2017 Sales $ 89,789 $ 3,071 Total expenses 80,662 1,373 Net income $ 9,127 $ 1,698 March 31, December 31, 2018 2017 Current assets $ 35,888 $ 38,344 Noncurrent assets 192,765 193,748 Current liabilities 25,601 24,710

Unit-Based Compensation (Tables

Unit-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2018
Unit-Based Compensation
Schedule Of Units Activity	Weighted Average Number of Grant Date Restricted Fair Value Units Per Unit Outstanding at December 31, 2017 283,138 $ 14.64 Granted — — Vested (171,231) 14.60 Returned/Cancelled (4,166) 13.59 Outstanding at March 31, 2018 107,741 $ 14.73

Distributions To Unitholders (T

Distributions To Unitholders (Tables)	3 Months Ended
	Mar. 31, 2018
Common units
Schedule of payment of cash distributions	Distribution Date of Date of Date of Three months ended per unit declaration record distribution March 31, 2017 $ 0.4375 May 10, 2017 May 22, 2017 May 31, 2017 June 30, 2017 $ 0.4441 August 9, 2017 August 22, 2017 August 31, 2017 September 30, 2017 $ 0.4508 November 7, 2017 November 20, 2017 November 30, 2017 December 31, 2017 $ 0.4508 February 8, 2018 February 20, 2018 February 28, 2018 March 31, 2018 $ 0.4508 May 8, 2018 May 22, 2018 May 31, 2018
Class B preferred units
Schedule of payment of cash distributions	Cash distribution Date of Date of Date of Three months ended per unit declaration record distribution March 31, 2017 (a) $ 0.2258 May 10, 2017 May 22, 2017 May 31, 2017 June 30, 2017 $ 0.28225 August 9, 2017 August 22, 2017 August 31, 2017 September 30, 2017 $ 0.28225 November 7, 2017 November 20, 2017 November 30, 2017 December 31, 2017 $ 0.28225 February 8, 2018 February 20, 2018 February 28, 2018 March 31, 2018 $ 0.28225 May 8, 2018 May 22, 2018 May 31, 2018 The Partnership elected to pay the first quarter 2017 distribution on the Class B preferred units in part cash and, with the consent of the Class B preferred unitholder, in part common units (in lieu of additional Class B preferred units). Accordingly, the Partnership declared a cash distribution of $0.2258 per Class B preferred unit and an aggregate distribution of 184,697 common units, each payable on May 31, 2017 to holders of record on May 22, 2017.

Partners' Capital (Tables)

Partners' Capital (Tables)	3 Months Ended
	Mar. 31, 2018
Partners' Capital
Class B preferred units accounted for as mezzanine equity in the consolidated balance sheet	The Class B Preferred Units are accounted for as mezzanine equity in the consolidated balance sheet consisting of the following (in thousands): March 31, December 31, 2018 2017 Mezzanine equity beginning balance $ 343,912 $ 342,991 Amortization of discount 531 1,796 Distributions 8,750 35,875 Distributions paid (8,750) (36,750) Total mezzanine equity $ 344,443 $ 343,912

Reporting Segments (Tables)

Reporting Segments (Tables)	3 Months Ended
	Mar. 31, 2018
Reporting Segments
Schedule of Segment Information	The following tables present financial information for each operating segment for the periods indicated based on the realignment of our operating segments (in thousands): Three Months Ended March 31, 2018 Production Midstream Total Segment revenues Natural gas sales $ 473 $ — $ 473 Oil sales 3,462 — 3,462 Natural gas liquid sales 595 — 595 Gathering and transportation sales — 1,688 1,688 Gathering and transportation lease revenues — 12,318 12,318 Total segment revenues 4,530 14,006 18,536 Segment operating costs Lease operating expenses 1,752 219 1,971 Transportation operating expenses — 2,847 2,847 Production taxes 322 — 322 Depreciation, depletion and amortization 1,363 5,265 6,628 Accretion expense 54 72 126 Total segment operating costs 3,491 8,403 11,894 Segment other income Earnings from equity investments — 4,272 4,272 Total segment other income — 4,272 4,272 Segment operating income $ 1,039 $ 9,875 $ 10,914 Three Months Ended March 31, 2017 Production Midstream Total Segment operating revenues Natural gas sales $ 2,779 $ — $ 2,779 Oil sales 11,350 — 11,350 Natural gas liquid sales 467 — 467 Gathering and transportation sales — 11,211 11,211 Total segment operating revenues 14,596 11,211 25,807 Segment operating costs Lease operating expenses 4,724 259 4,983 Transportation operating expenses — 3,296 3,296 Cost of sales 37 — 37 Production taxes 473 — 473 Depreciation, depletion and amortization 3,281 8,900 12,181 Asset impairments 4,688 — 4,688 Accretion expense 192 66 258 Total segment operating costs 13,395 12,521 25,916 Segment other income Earnings from equity investments (136) 618 482 Total segment other income (loss) (136) 618 482 Segment operating income (loss) $ 1,065 $ (692) $ 373
Summary of Total Assets by Operating Segment	Three Months Ended March 31, 2018 2017 Reconciliation of segment operating income to net income (loss) Total segment operating income $ 10,914 $ 373 General and administrative (5,165) (5,609) Unit-based compensation expense (1,438) (540) Interest expense, net (2,599) (1,883) Other income (expense) (a) (270) — Net income (loss) $ 1,442 $ (7,659) (a) Other expense in 2017 excludes earnout rebate. As the rebate is reviewed by the CODM at the segment level, it was included in the Midstream segment operating costs. The following table summarizes the total assets and capital expenditures by operating segment based on the segment realignment as of March 31, 2018 and 2017 (in thousands): March 31, 2018 Production Midstream Corporate (a) Total Other financial information Total assets $ 54,799 $ 455,388 $ 2,775 $ 512,962 Capital expenditures (b) $ 3 $ 701 $ — $ 704 December 31, 2017 Production Midstream Corporate (a) Total Other financial information Total assets $ 58,623 $ 468,656 $ 1,144 $ 528,423 Capital expenditures (b) $ 441 $ 46,452 $ — $ 46,893 (a) Corporate assets not reviewed by the CODM on a segment basis consists of cash, certain prepaids, office furniture, and other assets. (b) Inclusive of capital contributions made to equity method investments.

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	3 Months Ended
	Mar. 31, 2018
Variable Interest Entities
Schedule of Carrying Amounts of Assets and Liabilities of Variable Interest Entity	Below is a tabular comparison of the carrying amounts of the assets and liabilities of the VIE and the Partnership’s maximum exposure to loss as of March 31, 2018 and December 31, 2017 (in thousands): March 31, December 31, 2018 2017 Acquisitions and capital investments $ 125,323 $ 125,059 Earnings in equity investments 14,559 10,288 Distributions received (18,624) (11,632) Maximum exposure to loss $ 121,258 $ 123,715

Basis Of Presentation And Sum40

Basis Of Presentation And Summary Of Significant Accounting Policies (Details)	3 Months Ended
	Mar. 31, 2018segment
Basis Of Presentation And Summary Of Significant Accounting Policies
Number of operating segments	2

Revenue Recognition (Disaggrega

Revenue Recognition (Disaggregation) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Gathering and transportation lease revenues	$ 12,318
Total revenues	18,536	$ 25,807
Natural gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	473	2,779
Oil
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,462	11,350
Natural gas liquid
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	595	467
Gathering and transportation
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,688	11,211
Production
Disaggregation of Revenue [Line Items]
Total revenues	4,530
Production | Natural gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	473	2,779
Production | Oil
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,462	11,350
Production | Natural gas liquid
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	595	467
Midstream
Disaggregation of Revenue [Line Items]
Gathering and transportation lease revenues	12,318
Total revenues	14,006
Midstream | Gathering and transportation
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 1,688	$ 11,211

Revenue Recognition (Contract B

Revenue Recognition (Contract Balances) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Jan. 01, 2018
Revenue Recognition
Payment period	30 days
Receivables	$ 0.6	$ 1.1

Revenue Recognition (ASC 606) (

Revenue Recognition (ASC 606) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gathering and transportation lease revenues	$ 12,318
Total revenues	18,536	$ 25,807
Gathering and transportation
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue from contracts with customers	1,688	11,211
Midstream
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gathering and transportation lease revenues	12,318
Total revenues	14,006
Midstream | Accounting Standards Update 2014-09 | Balances without Adoption Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenues	14,006
Midstream | Accounting Standards Update 2014-09 | Effect of change Higher/(Lower)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gathering and transportation lease revenues	12,318
Midstream | Gathering and transportation
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue from contracts with customers	1,688	$ 11,211
Midstream | Gathering and transportation | Accounting Standards Update 2014-09 | Balances without Adoption Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue from contracts with customers	14,006
Midstream | Gathering and transportation | Accounting Standards Update 2014-09 | Effect of change Higher/(Lower)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue from contracts with customers	$ (12,318)

Acquisitions and Divestitures (

Acquisitions and Divestitures (Details) $ in Millions	1 Months Ended			3 Months Ended
	Oct. 31, 2017USD ($)	Sep. 30, 2017item	May 31, 2017USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)
Business Acquisition [Line Items]
Proved developed reserves (in mmcf/d) | item		400
Texas Production Divestiture
Business Acquisition [Line Items]
Proceeds from divestiture of business	$ 6.3
Gain on sale				$ 1.4
Oklahoma Production Divestiture
Business Acquisition [Line Items]
Proceeds from divestiture of business			$ 5.5
Gain on sale					$ 2.4

Fair Value Measurements (Recurr

Fair Value Measurements (Recurring) (Details) $ in Thousands	Mar. 31, 2018USD ($)derivative	Dec. 31, 2017USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Number of interest rate derivatives | derivative	0
Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative assets	$ (477)	$ 1,231
Derivative liabilities	(6,672)	(6,402)
Total net assets	(7,149)	(5,171)
Fair Value, Inputs, Level 2 | Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative assets	(477)	1,231
Total net assets	(477)	1,231
Fair Value, Inputs, Level 3 | Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative liabilities	(6,672)	(6,402)
Total net assets	$ (6,672)	$ (6,402)

Fair Value Measurements (Non-Re

Fair Value Measurements (Non-Recurring) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Asset impairments	$ 4,688
Fair Value, Inputs, Level 3 | Nonrecurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment		$ 7,277
Total net assets		$ 7,277

Fair Value Measurements (Embedd

Fair Value Measurements (Embedded and Earnout Derivative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Fair Value Measurements
Beginning Balance	$ (6,402)	$ (4,270)
Initial fair value of earnout derivative		221
Loss on earnout derivative	(270)	(2,353)
Ending Balance	$ (6,672)	$ (6,402)

Derivative And Financial Inst48

Derivative And Financial Instruments (Hedges In Place) (Details)	3 Months Ended
	Mar. 31, 2018MMBTU$ / bbl$ / MMBTUbbl
West Texas Intermediate 2018 Swap Quarter 2
Derivative [Line Items]
Volume (in Bbls) | bbl	66,432
Average Price | $ / bbl	59.71
West Texas Intermediate 2018 Swap Quarter 3
Derivative [Line Items]
Volume (in Bbls) | bbl	62,840
Average Price | $ / bbl	59.78
West Texas Intermediate 2018 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls) | bbl	59,704
Average Price | $ / bbl	59.84
West Texas Intermediate 2018
Derivative [Line Items]
Volume (in Bbls) | bbl	188,976
Average Price | $ / bbl	59.77
West Texas Intermediate 2019 Swap Quarter 1
Derivative [Line Items]
Volume (in Bbls) | bbl	62,528
Average Price | $ / bbl	60.41
West Texas Intermediate 2019 Swap Quarter 2
Derivative [Line Items]
Volume (in Bbls) | bbl	59,552
Average Price | $ / bbl	60.44
West Texas Intermediate 2019 Swap Quarter 3
Derivative [Line Items]
Volume (in Bbls) | bbl	57,024
Average Price | $ / bbl	60.48
West Texas Intermediate 2019 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls) | bbl	54,824
Average Price | $ / bbl	60.52
West Texas Intermediate 2019
Derivative [Line Items]
Volume (in Bbls) | bbl	233,928
Average Price | $ / bbl	60.46
West Texas Intermediate 2020 Swap Quarter 1
Derivative [Line Items]
Volume (in Bbls) | bbl	52,776
Average Price | $ / bbl	53.50
West Texas Intermediate 2020 Swap Quarter 2
Derivative [Line Items]
Volume (in Bbls) | bbl	50,960
Average Price | $ / bbl	53.50
West Texas Intermediate 2020 Swap Quarter 3
Derivative [Line Items]
Volume (in Bbls) | bbl	49,224
Average Price | $ / bbl	53.50
West Texas Intermediate 2020 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls) | bbl	47,624
Average Price | $ / bbl	53.50
West Texas Intermediate 2020
Derivative [Line Items]
Volume (in Bbls) | bbl	200,584
Average Price | $ / bbl	53.50
West Texas Intermediate
Derivative [Line Items]
Volume (in Bbls) | bbl	623,488
NYMEX 2018 Swap Quarter 2
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	126,600
Average Price | $ / MMBTU	3
NYMEX 2018 Swap Quarter 3
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	121,600
Average Price | $ / MMBTU	3
NYMEX 2018 Swap Quarter 4
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	117,040
Average Price | $ / MMBTU	3
NYMEX 2,018
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	365,240
Average Price | $ / MMBTU	3
NYMEX 2019 Swap Quarter 1
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	119,832
Average Price | $ / MMBTU	2.85
NYMEX 2019 Swap Quarter 2
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	115,784
Average Price | $ / MMBTU	2.85
NYMEX 2019 Swap Quarter 3
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	112,032
Average Price | $ / MMBTU	2.85
NYMEX 2019 Swap Quarter 4
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	108,552
Average Price | $ / MMBTU	2.85
NYMEX 2,019
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	456,200
Average Price | $ / MMBTU	2.85
NYMEX 2020 Swap Quarter 1
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	105,104
Average Price | $ / MMBTU	2.85
NYMEX 2020 Swap Quarter 2
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	102,008
Average Price | $ / MMBTU	2.85
NYMEX 2020 Swap Quarter 3
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	99,136
Average Price | $ / MMBTU	2.85
NYMEX 2020 Swap Quarter 4
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	96,200
Average Price | $ / MMBTU	2.85
NYMEX 2,020
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	402,448
Average Price | $ / MMBTU	2.85
NYMEX
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	1,223,888

Derivative And Financial Inst49

Derivative And Financial Instruments (Changes In Fair Value) (Details) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Aug. 31, 2017USD ($)	Mar. 31, 2018USD ($)item	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)
Derivative Instruments Gain Loss [Line Items]
Early termination of hedges	$ 3,600
Commodity Contract
Derivative Instruments Gain Loss [Line Items]
Beginning fair value of commodity derivatives		$ 1,231	$ 6,436	$ 6,436
Net gains (losses) on derivatives		(1,937)	6,055
Ending fair value of commodity derivatives		$ (477)		1,231
Number of counterparties | item		4
Oil reserves | Commodity Contract
Derivative Instruments Gain Loss [Line Items]
Net gains (losses) on derivatives		$ (1,939)	5,495	3,284
Net settlements paid (received) on derivative contracts				(6,422)
Net settlements paid (received) on derivative contracts		229
Natural gas | Commodity Contract
Derivative Instruments Gain Loss [Line Items]
Net gains (losses) on derivatives		$ 2	$ 560	663
Net settlements paid (received) on derivative contracts				$ (2,730)

Derivative And Financial Inst50

Derivative And Financial Instruments (Embedded Derivative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Derivative And Financial Instruments
Beginning Balance	$ (6,402)	$ (4,270)
Initial fair value of earnout derivative		221
Loss on earnout derivative	(270)	(2,353)
Ending Balance	(6,672)	(6,402)
Loss on earnout derivative	$ 270	$ 2,353

Derivative And Financial Inst51

Derivative And Financial Instruments (Effect On Statement Of Operations) (Details) - Commodity Contract - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Embedded Derivative [Line Items]
Net gains (losses) on derivatives	$ (1,937)	$ 6,055
Oil reserves
Embedded Derivative [Line Items]
Net gains (losses) on derivatives	(1,939)	5,495	$ 3,284
Natural gas
Embedded Derivative [Line Items]
Net gains (losses) on derivatives	$ 2	$ 560	$ 663

Long-Term Debt (Details)

Long-Term Debt (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)	May 19, 2016USD ($)
Line of Credit Facility [Line Items]
Letters of credit outstanding	$ 0
Amortization of debt issuance costs	131	$ 128
Unamortized debt issue costs	1,100		$ 1,200
Credit Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity	249,300
Credit agreement available	16,000
Sub-limit which may be used for issuance of letters of credit	$ 15,000
Borrowing base amount				$ 200,000
Commitment fee on unutilized borrowing base	0.50%
Credit agreement, outstanding	$ 184,000
Credit Agreement | Scenario One
Line of Credit Facility [Line Items]
Debt to Adjusted EBITDA ratio	5
Credit Agreement | Second full quarter after Catarina acquisition
Line of Credit Facility [Line Items]
Debt to Adjusted EBITDA ratio	4.75
Credit Agreement | Thereafter
Line of Credit Facility [Line Items]
Debt to Adjusted EBITDA ratio	4.5
Credit Facility Maturing March 31, 2020
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 500,000
lender loan
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 200,000
Minimum | Credit Agreement
Line of Credit Facility [Line Items]
Consolidated current asset ratio	1
Required interest coverage ratio	2.5
Distribution limitation, credit facility excess over borrowing base (as a percent)	90.00%
Ownership percentage by subsidiary	50
Minimum | Credit Agreement | Scenario One
Line of Credit Facility [Line Items]
Debt to Adjusted EBITDA ratio	4.5
Minimum | Credit Agreement | Scenario Two
Line of Credit Facility [Line Items]
Debt to Adjusted EBITDA ratio	4
Minimum | Credit Agreement | London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Variable interest rate	2.25%
Minimum | Credit Agreement | ABR
Line of Credit Facility [Line Items]
Variable interest rate	1.25%
Maximum | Credit Agreement | London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Variable interest rate	3.25%
Maximum | Credit Agreement | ABR
Line of Credit Facility [Line Items]
Variable interest rate	2.25%

Oil And Natural Gas Propertie53

Oil And Natural Gas Properties And Related Equipment (Gathering and Transportation Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Midstream assets	$ 185,407	$ 184,969
Less: Accumulated depreciation and amortization	(117,055)	(115,704)
Midstream
Property, Plant and Equipment [Line Items]
Midstream assets	185,407	184,969
Less: Accumulated depreciation and amortization	(28,770)	(26,870)
Total gathering and transportation assets	$ 156,637	$ 158,099

Oil And Natural Gas Propertie54

Oil And Natural Gas Properties And Related Equipment (Properties) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Oil And Natural Gas Properties And Related Equipment.
Proved property	$ 171,041	$ 170,750
Less: Accumulated depreciation, depletion, amortization and impairments	(117,055)	(115,704)
Oil and natural gas properties and equipment, net	$ 53,986	$ 55,046

Oil And Natural Gas Propertie55

Oil And Natural Gas Properties And Related Equipment (DDA and Impairments) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	Nov. 30, 2016item
Property, Plant and Equipment [Line Items]
Amortization of intangible assets	$ 3,365	$ 3,412
Depreciation, depletion and amortization	3,263	8,769
Asset impairments		4,688
Total	6,628	16,869
Non-cash impairment charges	$ 0
Gathering Facilities
Property, Plant and Equipment [Line Items]
Useful lives	36 years
Oil and Natural Gas-Related Assets
Property, Plant and Equipment [Line Items]
Depreciation, depletion and amortization	$ 1,363	3,234
Gathering and Transportation Related Assets
Property, Plant and Equipment [Line Items]
Depreciation, depletion and amortization	$ 1,900	5,535
Gathering and Transportation Related Assets | Minimum
Property, Plant and Equipment [Line Items]
Useful lives	3 years
Gathering and Transportation Related Assets | Maximum
Property, Plant and Equipment [Line Items]
Useful lives	15 years
Oil and Natural Gas-Related Assets and Gathering and Transportation-Related Assets
Property, Plant and Equipment [Line Items]
Depreciation, depletion and amortization	$ 6,628	$ 12,181
South Texas
Property, Plant and Equipment [Line Items]
Producing wellbores | item			23
Gonzales County, Texas
Property, Plant and Equipment [Line Items]
Producing wellbores | item			11

Asset Retirement Obligation (De

Asset Retirement Obligation (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Asset Retirement Obligation
Asset retirement obligation, beginning balance	$ 6,074	$ 13,579	$ 13,579
Liabilities added from escalating working interests	288		198
Sales			(8,416)
Settlements			(60)
Accretion expense	126	$ 258	773
Asset retirement obligation, ending balance	6,488		6,074
Legally restricted assets	$ 0		$ 0

Intangible Assets (Details)

Intangible Assets (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018USD ($)a	Dec. 31, 2017USD ($)
Finite-Lived Intangible Assets [Line Items]
Beginning balance	$ 172,166	$ 185,766
Disposals		(32)
Amortization	(3,365)	(13,568)
Ending balance	$ 168,801	$ 172,166
Customer Contracts
Finite-Lived Intangible Assets [Line Items]
Agreement term (in years)	15 years
Dedicated acreage | a	35,000
Useful life	15 years
Ending balance	$ 168,800

Investments (Details)

Investments (Details) - USD ($) $ in Thousands	Nov. 22, 2016	Jul. 05, 2016	Nov. 30, 2016	Jul. 31, 2016	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Capital investments					$ 125,323		$ 125,059
Earnings from equity investments					4,272	$ 482
Amortization of intangible assets					3,365	3,412
Distributions received					6,992	$ 2,010
Carnero Gathering, Joint Venture
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)		50.00%		50.00%
Payments to acquire interest in joint venture		$ 37,000		$ 37,000	46,400
Assumption of capital commitments in joint venture		$ 7,400		7,400
Capital investments					100
Earnout payments					0
Earnings from equity investments					2,200
Distributions received					2,600
Carnero Gathering, Joint Venture | Customer Relationships
Schedule of Equity Method Investments [Line Items]
Intangible asset, fair value				13,000
Amortization of intangible assets					200
Carnero Processing Joint Venture
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	50.00%		50.00%
Payments to acquire interest in joint venture	$ 55,500		$ 55,500		200
Assumption of capital commitments in joint venture	$ 24,500		24,500
Capital investments					74,900
Earnings from equity investments					2,300
Distributions received					$ 4,400
Sanchez Energy
Schedule of Equity Method Investments [Line Items]
Payments to acquire interest in joint venture			25,000
Assumption of capital commitments in joint venture			24,200
Sanchez Energy | Carnero Gathering, Joint Venture
Schedule of Equity Method Investments [Line Items]
Capital investments				$ 26,000
Sanchez Energy | Carnero Processing Joint Venture
Schedule of Equity Method Investments [Line Items]
Capital investments			$ 48,000
Targa | Carnero Gathering, Joint Venture
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)				50.00%
Targa | Carnero Processing Joint Venture
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)			50.00%

Investments (Unconsolidated Ent

Investments (Unconsolidated Entities) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Investments
Sales	$ 89,789	$ 3,071
Total expenses	80,662	1,373
Net income	9,127	$ 1,698
Current assets	35,888		$ 38,344
Noncurrent assets	192,765		193,748
Current liabilities	$ 25,601		$ 24,710

Commitments And Contingencies (

Commitments And Contingencies (Details) - Carnero Gathering, Joint Venture $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)
Variable Interest Entity [Line Items]
Earnout derivative liability	$ 6.7
Earnout payments	$ 0

Related Party Transactions (Det

Related Party Transactions (Details) $ in Millions	Sep. 01, 2017$ / MMBTU	Nov. 22, 2016USD ($)	Jul. 05, 2016USD ($)	Sep. 30, 2017item	Nov. 30, 2016USD ($)itemshares	Jul. 31, 2016USD ($)	Mar. 31, 2018USD ($)a$ / bbl$ / McfMcfbbl	Dec. 31, 2017USD ($)
Related Party Transaction [Line Items]
Related parties, net receivable							$ 6.1	$ 13.1
Related parties, net payable							$ 6.9	10.4
Proved developed reserves (in mmcf/d) | item				400
Agreed purchase price | $ / MMBTU	0.22
Ownership by related parties (as a percentage)							15.00%
Sanchez Energy
Related Party Transaction [Line Items]
Payments to acquire interest in joint venture					$ 25
Assumption of capital commitments in joint venture					$ 24.2
SP Holdings
Related Party Transaction [Line Items]
Quarterly fee (as a percent)							0.375%
Maximum asset acquisition, disposition and financing fee (as a percent)							2.00%
Agreement term (in years)							10 years
Services Agreement renewal term							10 years
Agreement notice period							180 days
Administrative fee paid							$ 2.3
Carnero Processing Joint Venture
Related Party Transaction [Line Items]
Ownership interest (as a percent)		50.00%			50.00%
Payments to acquire interest in joint venture		$ 55.5			$ 55.5		0.2
Assumption of capital commitments in joint venture		$ 24.5			$ 24.5
Carnero Gathering, Joint Venture
Related Party Transaction [Line Items]
Ownership interest (as a percent)			50.00%			50.00%
Payments to acquire interest in joint venture			$ 37			$ 37	46.4
Assumption of capital commitments in joint venture			$ 7.4			$ 7.4
Carnero Gathering, Joint Venture | Sanchez Energy
Related Party Transaction [Line Items]
Earnout payments to related parties							$ 0.1
Targa
Related Party Transaction [Line Items]
Ownership interest (as a percent)					50.00%
Eagle Ford | Sanchez Energy
Related Party Transaction [Line Items]
Acres dedicated for gathering | a							487,000
Net acres assembled | a							285,000
Acquisition of Wellbore Interests | Sanchez Energy
Related Party Transaction [Line Items]
Producing wellbores | item					23
Acquisition of Working Interests | Sanchez Energy
Related Party Transaction [Line Items]
Producing wellbores | item					11
Western Catarina Midstream | Sanchez Energy
Related Party Transaction [Line Items]
Agreement term (in years)							15 years
Acres dedicated for gathering | a							35,000
Gathering Agreement delivery commitment period							5 years
Proceeds from gathering and processing agreement							$ 14	$ 12.6
Western Catarina Midstream | Sanchez Energy | Oil reserves
Related Party Transaction [Line Items]
Gathering Agreement minimum quarterly volume delivery commitment | bbl							10,200
Gathering and processing fees (in dollars per volume) | $ / bbl							0.96
Western Catarina Midstream | Sanchez Energy | Natural gas
Related Party Transaction [Line Items]
Gathering Agreement minimum quarterly volume delivery commitment | Mcf							142,000
Gathering and processing fees (in dollars per volume) | $ / Mcf							0.74
Western Catarina Midstream | SN Catarina | Oil reserves
Related Party Transaction [Line Items]
Proceeds from transportation agreement							$ 0.5
Common units | Sanchez Energy
Related Party Transaction [Line Items]
Shares repurchased | shares					2,272,727
Common units | Sanchez Energy | Executive Chairman
Related Party Transaction [Line Items]
Ownership by related parties (as a percentage)							6.80%
Common units | Sanchez Energy | Chief Executive Officer
Related Party Transaction [Line Items]
Ownership by related parties (as a percentage)							3.00%
Common units | Sanchez Energy | President
Related Party Transaction [Line Items]
Ownership by related parties (as a percentage)							1.20%

Unit-Based Compensation (Restri

Unit-Based Compensation (Restricted Units Activity) (Details) - LTIP - $ / shares	1 Months Ended	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units available for issuance		1,634,947
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Restricted Units, Outstanding		283,138
Number of Restricted Units, Granted	171,231
Number of Restricted Units, Vested		(171,231)
Number of Restricted Units, Returned/Cancelled		(4,166)
Number of Restricted Units, Outstanding		107,741
Weighted Averaged Grant Date Fair Value Per Unit, Outstanding		$ 14.64
Weighted Averaged Grant Date Fair Value Per Unit, Vested		14.60
Weighted Averaged Grant Date Fair Value Per Unit, Returned/Cancelled		13.59
Weighted Averaged Grant Date Fair Value Per Unit, Outstanding		$ 14.73

Distributions To Unitholders (D

Distributions To Unitholders (Details) - $ / shares	May 31, 2017	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2017
Common units
Distribution paid per unit		$ 0.4508	$ 0.4508	$ 0.4508	$ 0.4441	$ 0.4375
Aggregate distribution of units							393,291
Class B preferred units
Distribution paid per unit		$ 0.28225	$ 0.28225	$ 0.28225	$ 0.28225	$ 0.2258
Aggregate distribution of units	184,697

Partners' Capital (Details)

Partners' Capital (Details) - USD ($) $ / shares in Units, $ in Millions	May 22, 2017	Jan. 25, 2017	Oct. 14, 2015	Apr. 30, 2017	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015	Dec. 06, 2016
Limited Partners' Capital Account [Line Items]
Class B preferred units, outstanding					31,000,887	31,000,887
Common units, outstanding					15,171,946	14,965,134
Units, issued					15,171,946	14,965,134
Class B preferred units, issued					31,000,887	31,000,887
Class B preferred units
Limited Partners' Capital Account [Line Items]
Class B preferred units, outstanding					31,000,887
Units, issued													9,851,996
Units sold (in units)	184,697		19,444,445
Price per unit sold			$ 18
Proceeds from preferred units sold			$ 350
Percent of consideration paid			2.25%
Paid in full in cash, per annum												10.00%
Paid in part cash, per annum												12.00%
Dividend per annum												8.00%
Paid-in kind units per annum												4.00%
Class B preferred units | Settlement Agreement with Stonepeak Catarina Holdings LLC
Limited Partners' Capital Account [Line Items]
Class B preferred units, issued		1,704,446
Class B preferred units, unit price		$ 11.29
Common units
Limited Partners' Capital Account [Line Items]
Common units, outstanding					15,171,946
Units, issued				84,577
Units sold (in units)						210,978	186,942	170,497	139,110	154,737	170,750
Proceeds from common units sold				$ 1.3
Common units authorized for sale, value				$ 50
Minimum | Class B preferred units
Limited Partners' Capital Account [Line Items]
Preferred unit conversion, amount					$ 17.5

Partners' Capital (Class B Pref

Partners' Capital (Class B Preferred Units) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Mezzanine equity beginning balance	$ 343,912
Distributions	8,750	$ 7,000
Total mezzanine equity	344,443		$ 343,912
Class B preferred units
Mezzanine equity beginning balance	343,912	$ 342,991	342,991
Amortization of discount	531		1,796
Distributions	8,750		35,875
Distributions paid	(8,750)		(36,750)
Total mezzanine equity	$ 344,443		$ 343,912

Partners' Capital (EPU) (Detail

Partners' Capital (EPU) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Partners' Capital
Weighted Average Units Outstanding, Common Units - Basic and Diluted (in units)	14,738,528	13,400,138
Assumed net loss to be allocated	$ (7,839)	$ (17,688)
Basic and diluted loss per unit (in dollars per share)	$ (0.53)	$ (1.32)
Asset impairments		$ 4,688

Reporting Segments (Segment Inf

Reporting Segments (Segment Information) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Segment operating revenues:
Gathering and transportation lease revenues	$ 12,318
Total revenues	18,536	$ 25,807
Segment operating costs:
Lease operating expenses	1,971	4,983
Transportation operating expenses	2,847	3,296
Cost of sales		37
Production taxes	322	473
Depreciation, depletion and amortization	6,628	12,181
Asset impairments		4,688
Accretion expense	126	258	$ 773
Total operating expenses	18,497	32,065
Segment other income
Earnings from equity investments	4,272	482
Total segment other income (loss)	4,272	482
Segment operating income	10,914	373
Production
Segment operating revenues:
Total revenues	4,530
Segment operating costs:
Lease operating expenses	1,752	4,724
Cost of sales		37
Production taxes	322	473
Depreciation, depletion and amortization	1,363	3,281
Asset impairments		4,688
Accretion expense	54	192
Segment other income
Earnings from equity investments		(136)
Total segment other income (loss)		(136)
Segment operating income	1,039	1,065
Midstream
Segment operating revenues:
Gathering and transportation lease revenues	12,318
Total revenues	14,006
Segment operating costs:
Lease operating expenses	219	259
Transportation operating expenses	2,847	3,296
Depreciation, depletion and amortization	5,265	8,900
Accretion expense	72	66
Segment other income
Earnings from equity investments	4,272	618
Total segment other income (loss)	4,272	618
Segment operating income	9,875	(692)
Operating Segments
Segment operating revenues:
Total revenues		25,807
Segment operating costs:
Total operating expenses	11,894	25,916
Operating Segments | Production
Segment operating revenues:
Total revenues		14,596
Segment operating costs:
Total operating expenses	3,491	13,395
Operating Segments | Midstream
Segment operating revenues:
Total revenues		11,211
Segment operating costs:
Total operating expenses	8,403	12,521
Natural gas
Segment operating revenues:
Revenue from contracts with customers	473	2,779
Natural gas | Production
Segment operating revenues:
Revenue from contracts with customers	473	2,779
Oil
Segment operating revenues:
Revenue from contracts with customers	3,462	11,350
Oil | Production
Segment operating revenues:
Revenue from contracts with customers	3,462	11,350
Natural gas liquid
Segment operating revenues:
Revenue from contracts with customers	595	467
Natural gas liquid | Production
Segment operating revenues:
Revenue from contracts with customers	595	467
Gathering and transportation
Segment operating revenues:
Revenue from contracts with customers	1,688	11,211
Gathering and transportation | Midstream
Segment operating revenues:
Revenue from contracts with customers	$ 1,688	$ 11,211

Reporting Segments - Reconcilia

Reporting Segments - Reconciliation of Segment Operating Income (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Reconciliation of segment operating income to net income (loss):
Segment operating income	$ 10,914	$ 373
General and administrative	(5,165)	(5,609)
Unit-based compensation expense	(1,438)	(540)
Interest expense, net	(2,599)	(1,883)
Other income (expense)	(270)
Net income (loss)	$ 1,442	$ (7,659)	$ (3,040)

Reporting Segments (Assets by S

Reporting Segments (Assets by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 512,962	$ 528,423	$ 528,423
Capital expenditures	704	46,893
Production
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	54,799	58,623
Capital expenditures	3	441
Midstream
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	455,388	468,656
Capital expenditures	701	46,452
Corporate
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 2,775	$ 1,144

Variable Interest Entities (Det

Variable Interest Entities (Details) - USD ($) $ in Thousands	Nov. 22, 2016	Jul. 05, 2016	Nov. 30, 2016	Jul. 31, 2016	Mar. 31, 2018	Dec. 31, 2017
Variable Interest Entity [Line Items]
Capital investments					$ 125,323	$ 125,059
Earnings in equity investments					14,559	10,288
Distributions received					(18,624)	(11,632)
Maximum exposure to loss					121,258	$ 123,715
Carnero Gathering, Joint Venture
Variable Interest Entity [Line Items]
Ownership interest (as a percent)		50.00%		50.00%
Payments to acquire interest in joint venture		$ 37,000		$ 37,000	46,400
Assumption of capital commitments in joint venture		$ 7,400		$ 7,400
Debt incurred					0
Capital investments					100
Maximum exposure to loss					47,400
Carnero Processing Joint Venture
Variable Interest Entity [Line Items]
Ownership interest (as a percent)	50.00%		50.00%
Payments to acquire interest in joint venture	$ 55,500		$ 55,500		200
Assumption of capital commitments in joint venture	$ 24,500		$ 24,500
Debt incurred					0
Capital investments					74,900
Maximum exposure to loss					$ 73,900

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent event - USD ($) $ / shares in Units, $ in Millions	May 08, 2018	Apr. 30, 2018
Common units
Subsequent Event [Line Items]
Distribution declared per unit	$ 0.4508
Annual distribution declared per unit	1.8032
Class B preferred units
Subsequent Event [Line Items]
Distribution declared per unit	$ 0.28225
SEP Holdings IV, LLC | The Briggs Assets
Subsequent Event [Line Items]
Purchase price for acquisition		$ 4.5
Purchase price after adjustments		$ 4