Oasis Midstream Partners (OMP) 10-Q 4 Nov 21 2021 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2021	Nov. 02, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-38212
Entity Registrant Name	Oasis Midstream Partners LP
Entity Incorporation State	DE
Entity Tax Identification Number	47-1208855
Entity Address, Address Line One	1001 Fannin Street
Entity Address, Address Line Two	Suite 1500
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77002
City Area Code	281
Local Phone Number	404-9500
Title of 12(b) Security	Common units representing limited partner interests
Trading Symbol	OMP
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Shell Company	false
Entity Bankruptcy Proceedings, Reporting Current	true
Entity Common Stock, Shares Outstanding		48,627,680
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001652133
Current Fiscal Year End Date	--12-31

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 29,682	$ 5,147
Accounts receivable	5,218	4,295
Accounts receivable – Oasis Petroleum	60,895	66,283
Inventory	5,828	6,986
Prepaid expenses	1,040	3,695
Other current assets	152	649
Total current assets	102,815	87,055
Property, plant and equipment	1,210,306	1,180,819
Less: accumulated depreciation, amortization and impairment	(268,549)	(240,877)
Total property, plant and equipment, net	941,757	939,942
Operating lease right-of-use assets	917	1,643
Other assets	2,599	2,053
Total assets	1,048,088	1,030,693
Current liabilities
Accounts payable	1,734	2,226
Accounts payable – Oasis Petroleum	6,688	28,074
Accrued liabilities	34,290	17,931
Accrued interest payable	18,412	360
Current operating lease liabilities	973	945
Other current liabilities	685	471
Total current liabilities	62,782	50,007
Long-term debt	650,390	450,000
Asset retirement obligations	825	774
Operating lease liabilities	0	733
Other liabilities	7,600	5,521
Total liabilities	721,597	507,035
Commitments and contingencies (Note 9)
Equity
General Partner	0	1,027
Total partners’ equity	326,491	238,593
Non-controlling interests	0	285,065
Total equity	326,491	523,658
Total liabilities and equity	1,048,088	1,030,693
Common Units
Equity
Limited partners	326,491	193,536
Subordinated Units
Equity
Limited partners	$ 0	$ 44,030

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - shares	Sep. 30, 2021	Dec. 31, 2020
Common Units
Units issued (in shares)	48,627,680	20,061,366
Units outstanding (in shares)	48,627,680	20,061,366
Subordinated Units
Units issued (in shares)	0	13,750,000
Units outstanding (in shares)	0	13,750,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenues
Total revenues	$ 105,375	$ 84,555	$ 301,003	$ 257,245
Operating expenses
Costs of product sales	26,065	5,958	67,991	16,605
Operating and maintenance	14,679	12,682	40,006	44,030
Depreciation and amortization	9,357	9,083	27,759	31,161
Impairment	0	1,458	2	103,441
General and administrative	6,596	8,870	23,128	26,607
Total operating expenses	56,697	38,051	158,886	221,844
Operating income	48,678	46,504	142,117	35,401
Other income (expense)
Interest expense, net of capitalized interest	(11,081)	(2,753)	(26,372)	(38,196)
Other income (expense)	23	(7)	(45)	(150)
Total other expenses	(11,058)	(2,760)	(26,417)	(38,346)
Net income (loss)	37,620	43,744	115,700	(2,945)
Less: Net income attributable to non-controlling interests	0	16,483	17,025	29,319
Net income (loss) attributable to Oasis Midstream Partners LP	37,620	27,261	98,675	(32,264)
Less: Net income attributable to General Partner	0	1,027	0	3,062
Net income (loss) attributable to limited partners	$ 37,620	$ 26,234	$ 98,675	$ (35,326)
Earnings (loss) per limited partner unit (Note 11)
Common units - basic (in usd per share)	$ 0.77	$ 0.78	$ 2.23	$ (1.05)
Common units - diluted (in usd per share)	$ 0.77	$ 0.78	$ 2.23	$ (1.05)
Weighted average number of limited partners units outstanding (Note 11)
Common units - basic (in shares)	48,570	20,045	39,829	20,044
Common units - diluted (in shares)	48,599	20,048	39,858	20,044
Midstream service revenues
Revenues
Total revenues	$ 71,355	$ 69,354	$ 205,670	$ 217,381
Midstream service revenues | Oasis Petroleum
Revenues
Total revenues	65,859	67,401	198,087	206,340
Midstream service revenues | Third Parties
Revenues
Total revenues	5,496	1,953	7,583	11,041
Product revenues
Revenues
Total revenues	34,020	15,201	95,333	39,864
Product revenues | Oasis Petroleum
Revenues
Total revenues	33,769	15,184	95,042	39,841
Product revenues | Third Parties
Revenues
Total revenues	$ 251	$ 17	$ 291	$ 23

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Changes in Equity (Unaudited) - USD ($) $ in Thousands	Total	Non-controlling Interests	UnitholdersCommon Units	UnitholdersSubordinated Units	General Partner
Beginning balance at Dec. 31, 2019	$ 604,628	$ 312,258	$ 225,339	$ 66,005	$ 1,026
Increase (Decrease) in Partners' Capital [Roll Forward]
Contributions from non-controlling interests	6,167	6,167
Distributions to non-controlling interests	(25,964)	(25,964)
Distributions to unitholders	(19,265)		(10,833)	(7,425)	(1,007)
Equity-based compensation	66		66
Net income	(69,359)	2,040	(42,947)	(29,460)	1,008
Ending balance at Mar. 31, 2020	496,273	294,501	171,625	29,120	1,027
Beginning balance at Dec. 31, 2019	604,628	312,258	225,339	66,005	1,026
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	(2,945)
Ending balance at Sep. 30, 2020	489,176	286,704	172,087	29,358	1,027
Beginning balance at Mar. 31, 2020	496,273	294,501	171,625	29,120	1,027
Increase (Decrease) in Partners' Capital [Roll Forward]
Contributions from non-controlling interests	309	309
Distributions to non-controlling interests	(14,335)	(14,335)
Distributions to unitholders	(19,285)		(10,833)	(7,425)	(1,027)
Equity-based compensation	67		67
Net income	22,670	10,796	6,433	4,414	1,027
Ending balance at Jun. 30, 2020	485,699	291,271	167,292	26,109	1,027
Increase (Decrease) in Partners' Capital [Roll Forward]
Contributions from non-controlling interests	(1,077)	(1,077)
Distributions to non-controlling interests	(19,973)	(19,973)
Distributions to unitholders	(19,285)		(10,833)	(7,425)	(1,027)
Equity-based compensation	68		68
Net income	43,744	16,483	15,560	10,674	1,027
Ending balance at Sep. 30, 2020	489,176	286,704	172,087	29,358	1,027
Beginning balance at Dec. 31, 2020	523,658	285,065	193,536	44,030	1,027
Increase (Decrease) in Partners' Capital [Roll Forward]
Contributions from non-controlling interests	6	6
Distributions to non-controlling interests	(7,615)	(7,615)
Distributions to unitholders	(19,294)		(10,842)	(7,425)	(1,027)
Conversion of Subordinated Units to Common Units	0		45,808	(45,808)
Distribution to Oasis for Simplification Transaction	(231,509)		(231,509)
Elimination of non-controlling interests for Simplification Transaction	0	(294,481)	294,481
Common control transaction costs	(811)		(811)
Equity-based compensation	487		487
Net income	42,926	17,025	16,698	9,203
Ending balance at Mar. 31, 2021	307,848	0	307,848	0	0
Beginning balance at Dec. 31, 2020	523,658	285,065	193,536	44,030	1,027
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	115,700
Ending balance at Sep. 30, 2021	326,491	0	326,491	0	0
Beginning balance at Mar. 31, 2021	307,848	0	307,848	0	0
Increase (Decrease) in Partners' Capital [Roll Forward]
Distributions to unitholders	(26,745)		(26,745)
Common control transaction costs	50		50
Issuance of common units, net of offering costs	86,657		86,657
Redemption of common units	(86,957)		(86,957)
Equity-based compensation	16		16
Net income	35,154		35,154
Ending balance at Jun. 30, 2021	316,023	0	316,023	0	0
Increase (Decrease) in Partners' Capital [Roll Forward]
Distributions to unitholders	(27,232)		(27,232)
Other	(64)		(64)
Equity-based compensation	144		144
Net income	37,620		37,620
Ending balance at Sep. 30, 2021	$ 326,491	$ 0	$ 326,491	$ 0	$ 0

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net income (loss)	$ 115,700	$ (2,945)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	27,759	31,161
Impairment	2	103,441
Equity-based compensation expenses	647	201
Deferred financing costs amortization and other	2,241	815
Working capital and other changes:
Change in accounts receivable	4,465	16,270
Change in inventory	1,156	(8,440)
Change in prepaid expenses	2,655	(1,014)
Change in other current assets	499	0
Change in accounts payable and accrued liabilities	2,146	27,080
Change in other assets and liabilities, net	2,870	(164)
Net cash provided by operating activities	160,140	166,405
Cash flows from investing activities:
Capital expenditures	(20,511)	(52,163)
Net cash used in investing activities	(20,511)	(52,163)
Cash flows from financing activities:
Capital contributions from non-controlling interests	6	5,399
Distributions to Oasis for Simplification Transaction	(231,509)	0
Distributions to non-controlling interests	(7,615)	(60,272)
Distributions to unitholders	(73,271)	(57,835)
Common control transaction costs	(761)	0
Proceeds from issuance of common units, net of offering costs	86,592	0
Redemption of common units	(86,957)	0
Proceeds from issuance of senior notes	450,000	0
Deferred financing costs	(11,579)	0
Borrowings on revolving credit facility	39,500	29,000
Payments on revolving credit facility	(279,500)	0
Other	0	(3)
Net cash used in financing activities	(115,094)	(83,711)
Increase in cash and cash equivalents	24,535	30,531
Cash:
Beginning of period	5,147	4,168
End of period	29,682	34,699
Supplemental cash flow information:
Cash paid for interest, net of capitalized interest	6,040	9,826
Supplemental non-cash transactions:
Change in accrued capital expenditures	8,976	(29,751)
Change in asset retirement obligations	$ 51	$ 61

Organization and Nature of Oper

Organization and Nature of Operations	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Nature of Operations	Organization and Nature of Operations Organization. Oasis Midstream Partners LP (the “Partnership”) is a leading gathering and processing master limited partnership formed by its sponsor, Oasis Petroleum Inc. (together with its subsidiaries, “Oasis Petroleum”) to own, develop, operate and acquire a diversified portfolio of midstream assets in North America. The Partnership conducts its business through its wholly-owned subsidiaries: Bighorn DevCo LLC (“Bighorn DevCo”), Bobcat DevCo LLC (“Bobcat DevCo”), Beartooth DevCo LLC (“Beartooth DevCo”) and Panther DevCo LLC (“Panther DevCo” and collectively with Bighorn DevCo, Bobcat DevCo and Beartooth DevCo, the “DevCos”). As of September 30, 2021, the Partnership’s assets in the DevCos were as follows: DevCo Areas Served Service Lines Bighorn DevCo Wild Basin – Natural gas processing – Crude oil terminaling – Crude oil transportation – Crude oil gathering Bobcat DevCo Wild Basin – Natural gas gathering – Natural gas compression – Gas lift supply – Crude oil gathering – Produced and flowback water gathering – Produced and flowback water disposal Beartooth DevCo Alger – Produced and flowback water gathering – Produced and flowback water disposal – Freshwater supply and distribution Panther DevCo Permian Basin – Crude oil gathering – Produced and flowback water gathering – Produced and flowback water disposal Nature of business. The Partnership generates a substantial majority of its revenues through fee-based contractual arrangements with Oasis Petroleum for midstream services. These services include (i) gas gathering, compression, processing, gas lift supply and natural gas liquids (“NGLs”) storage services; (ii) crude oil gathering, terminaling and transportation services; (iii) produced and flowback water gathering and disposal services; and (iv) freshwater supply and distribution services. The revenue earned from these services is generally directly related to the volume of natural gas, crude oil, produced and flowback water and freshwater that flows through the Partnership’s systems. The Partnership’s operations are supported by significant acreage dedications from Oasis Petroleum and commitments from third party producers in the Williston Basin and Permian Basin. On June 29, 2021, Oasis Petroleum sold its remaining upstream assets in the Permian Basin to a third party buyer. The Partnership retained its midstream assets in the Permian Basin through its ownership of Panther DevCo, and all of its midstream services in the Permian Basin are now provided to third party producers. Upon closing, the commercial agreements between Panther DevCo and Oasis Petroleum were assigned to the buyer, and there were no material changes to the terms of such agreements.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying condensed consolidated financial statements of the Partnership have not been audited by the Partnership’s independent registered public accounting firm, except that the Condensed Consolidated Balance Sheet at December 31, 2020 is derived from audited financial statements. In the opinion of management, all adjustments, consisting of normal recurring adjustments necessary for fair statement of the Partnership’s financial position have been included. Management has made certain estimates and assumptions that affect reported amounts in the condensed consolidated financial statements and disclosures of contingencies. Actual results may differ from those estimates. The results for interim periods are not necessarily indicative of annual results. These interim financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Certain disclosures have been condensed or omitted from these financial statements. Accordingly, they do not include all of the information and notes required by accounting principles generally accepted in the United States of America (“GAAP”) for complete consolidated financial statements and should be read in conjunction with the Partnership’s audited consolidated financial statements and notes thereto included in the Partnership’s Annual Report on Form 10-K for the year ended December 31, 2020 (“2020 Annual Report”). Simplification Transaction On March 30, 2021, the Partnership closed the Simplification Transaction (defined below) with Oasis Petroleum to acquire Oasis Petroleum’s remaining ownership interests in Bobcat DevCo and Beartooth DevCo. In addition, the Simplification Transaction eliminated the incentive distribution rights (the “IDRs”) held by the General Partner (see Note 4 — Transactions with Affiliates). Prior to the Simplification Transaction, the Contributed Assets (defined below) were reflected as non-controlling interests in the Partnership’s unaudited condensed consolidated financial statements. In accordance with the Financial Accounting Standard Board’s (“FASB”) authoritative guidance under Accounting Standards Codification (“ASC”) Topic 810-10 for non-controlling interests in a common control transaction, the Partnership accounted for the Simplification Transaction as an equity transaction and adjusted the carrying amount of non-controlling interests in the condensed consolidated financial statements to reflect the change in ownership interests. Furthermore, as the Partnership acquired additional interests in previously consolidated subsidiaries, the Simplification Transaction did not result in a change in reporting entity, as defined under the FASB authoritative guidance under ASC Topic 805, Business Combinations , and was accounted for on a prospective basis. Consolidation The Partnership’s condensed consolidated financial statements include its accounts and the accounts of the DevCos, each of which is a wholly-owned subsidiary of the Partnership and controlled by the Partnership through OMP GP LLC (the “General Partner”). All intercompany balances and transactions have been eliminated upon consolidation. Risks and Uncertainties Concentrations of market and credit risk. The Partnership has limited direct exposure to risks associated with fluctuating commodity prices due to the nature of its business and its long-term, fixed-fee contractual arrangements with its existing customers, including Oasis Petroleum. However, to the extent that the Partnership’s future contractual arrangements with customers, including Oasis Petroleum or third parties, do not provide for fixed-fee structures, the Partnership may become subject to more substantial direct commodity price risk. In addition, in response to a prolonged low commodity price environment, the Partnership’s customers could seek to amend existing contractual arrangements to reduce the volumetric fees the Partnership charges. As a substantial majority of the Partnership’s revenues are derived from Oasis Petroleum, the Partnership is indirectly subject to risks associated with fluctuating commodity prices to the extent that lower commodity prices adversely affect Oasis Petroleum’s production, drilling schedule or financial condition. Significant Accounting Policies There have been no material changes to the Partnership’s critical accounting policies and estimates from those disclosed in the 2020 Annual Report. Recent Accounting Pronouncements Reference rate reform. In March 2020, the FASB issued Accounting Standards Update 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting (“ASU 2020-04”). The amendments provide

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition Disaggregation of Revenues The following table presents revenues associated with contracts with customers for the periods presented: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (In thousands) Service revenues Crude oil, natural gas and NGL revenues $ 46,889 $ 43,137 $ 135,546 $ 138,226 Produced and flowback water revenues 24,466 26,217 70,124 79,155 Total service revenues 71,355 69,354 205,670 217,381 Product revenues Crude oil, natural gas and NGL revenues 32,187 13,863 88,378 31,165 Freshwater revenues 1,833 1,338 6,955 8,699 Total product revenues 34,020 15,201 95,333 39,864 Total revenues $ 105,375 $ 84,555 $ 301,003 $ 257,245 Prior Period Performance Obligations The Partnership records revenue when the performance obligations under the terms of its customer contracts are satisfied. The Partnership measures the satisfaction of its performance obligations using the output method based upon the volumes of crude oil, natural gas or water that flow through its systems. In certain cases, the Partnership is required to estimate these volumes during a reporting period and record any differences between the estimated volumes and actual volumes in the following reporting period. Such differences have historically not been significant. For the three and nine months ended September 30, 2021 and 2020, revenues recognized related to performance obligations satisfied in prior reporting periods were not material. Contract Balances Contract balances are the result of timing differences between revenue recognition, billings and cash collections. Contract assets relate to revenue recognized for accrued deficiency fees associated with minimum volume commitments where the Partnership believes it is probable there will be a shortfall payment and that a significant reversal of revenue recognized will not occur once the related performance period is completed and the customer is billed. Contract liabilities relate to aid in construction payments received from customers, which are recognized as revenue over the expected period of future benefit. The Partnership does not recognize contract assets or contract liabilities under its customer contracts for which invoicing occurs once the Partnership’s performance obligations have been satisfied and payment is unconditional. Contract balances are classified as current or long-term based on the timing of when the Partnership expects to receive cash for contract assets or recognize revenue for contract liabilities. The Partnership did not have any material contract asset balances as of September 30, 2021 or December 31, 2020. The following table summarizes the changes in contract liabilities for the nine months ended September 30, 2021: (In thousands) Balance as of December 31, 2020 $ 5,421 Cash received 3,231 Revenue recognized (367) Balance as of September 30, 2021 $ 8,285 Remaining Performance Obligations The following table presents estimated revenue allocated to remaining performance obligations for contracted revenues that are unsatisfied (or partially satisfied) as of September 30, 2021: (In thousands) 2021 (excluding nine months ended September 30, 2021) $ 3,709 2022 17,175 2023 10,896 2024 11,089 2025 2,768 Total $ 45,637 The partially and wholly unsatisfied performance obligations presented in the table above are generally limited to customer contracts which have fixed pricing and fixed volume terms and conditions, which generally include customer contracts with minimum volume commitment payment obligations. The Partnership has elected practical expedients, pursuant to ASC 606, Revenue from Contracts with Customers , to exclude from the presentation of remaining performance obligations: (i) contracts with index-based pricing or variable volume attributes in which such variable consideration is allocated entirely to a wholly unsatisfied performance obligation or to a wholly unsatisfied promise to transfer a distinct service that forms part of a series of distinct services and (ii) contracts with an original expected duration of one year or less.

Transactions with Affiliates

Transactions with Affiliates	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Transactions with Affiliates	Transactions with Affiliates Revenues. The Partnership generates the substantial majority of its revenues through fee-based contractual arrangements with wholly-owned subsidiaries of Oasis Petroleum for midstream services as described in Note 1 — Organization and Nature of Operations. In addition, the Partnership sells the residue gas and NGLs recovered from its gas processing plants attributable to its third-party natural gas purchase agreements to Oasis Petroleum to market and sell to non-affiliated purchasers. Expenses. Oasis Petroleum provides substantial labor and overhead support to the Partnership pursuant to a services and secondment agreement. Oasis Petroleum performs centralized corporate, general and administrative services for the Partnership, such as legal, corporate recordkeeping, planning, budgeting, regulatory, accounting, billing, business development, treasury, insurance administration and claims processing, risk management, health, safety and environmental, information technology, human resources, investor relations, cash management and banking, payroll, internal audit, tax and engineering. Oasis Petroleum has also seconded to the Partnership certain of its employees to operate, construct, manage and maintain the Partnership’s assets. The expenses of executive officers and non-executive employees of Oasis Petroleum are allocated to the Partnership based on the amount of time spent managing its business and operations. The Partnership reimburses Oasis Petroleum for direct and allocated general and administrative expenses incurred by Oasis Petroleum for the provision of these services. The Partnership’s general and administrative expenses include $5.6 million and $7.9 million from affiliate transactions with Oasis Petroleum for the three months ended September 30, 2021 and 2020, respectively, and $19.5 million and $23.6 million from affiliate transactions with Oasis Petroleum for the nine months ended September 30, 2021 and 2020, respectively. Simplification Transaction. On March 30, 2021, the Partnership consummated the transactions contemplated by the Contribution and Simplification Agreement (the “Contribution and Simplification Agreement”), dated as of March 22, 2021, by and among the Partnership, OMS Holdings LLC (“OMS Holdings”), Oasis Midstream Services LLC (“OMS”), the General Partner, OMP Operating LLC (“OMP Operating”), OMP DevCo Holdings Corp, Beartooth DevCo LLC (“Beartooth DevCo”), Bobcat DevCo LLC (“Bobcat DevCo”), OMS Holdings Merger Sub, LLC, a wholly-owned subsidiary of OMS Holdings, and for limited purposes set forth therein, Oasis Petroleum. Pursuant to the Contribution and Simplification Agreement, among other things, (a) Oasis Petroleum contributed to the Partnership its remaining limited liability company interests in Bobcat DevCo and Beartooth DevCo of 64.7% and 30.0% (the “Contributed Assets”), respectively, in exchange for total consideration of $512.5 million composed of (x) a cash distribution of $231.5 million, sourced from the net proceeds of the offering of the Senior Notes (defined below) and (y) 12,949,644 common units representing limited partner interests in the Partnership, (b) the Partnership’s IDRs were cancelled and converted into 1,850,356 common units representing limited partner interests in the Partnership (the “IDR Elimination” and such common units, the “IDR Conversion Common Units”), and (c) the IDR Conversion Common Units were distributed on a pro-rata basis by the General Partner to the holders of its Class A Units and Class B Units, such that following such distribution, Oasis Petroleum, through its wholly-owned subsidiary OMS Holdings, is the sole member of the General Partner (the foregoing clauses (a), (b) and (c), the “Simplification Transaction”). The Contribution and Simplification Agreement also implemented among other things, a right of first refusal in favor of the Partnership with respect to the midstream opportunities in the Painted Woods and City of Williston operating areas of Oasis Petroleum and the amendment and restatement of the (x) agreement of limited partnership of the Partnership and (y) limited liability company agreement of the General Partner to reflect the Simplification Transaction. The effective date of the Simplification Transaction was January 1, 2021 and was accounted for on the closing date of March 30, 2021. As a result, net income was allocated to Oasis Petroleum’s non-controlling interests in Bobcat DevCo and Beartooth DevCo until the closing date. The cash distribution to Oasis Petroleum of $231.5 million includes: (i) $229.0 million cash component of the purchase price, (ii) $10.1 million upward adjustment to the purchase price related to the expanded project dedication to the Partnership in South Nesson and (iii) $7.6 million downward adjustment to the purchase price related to activity between the effective date and the close date. At March 30, 2021, Oasis Petroleum’s non-controlling interests in Bobcat DevCo and Beartooth DevCo were eliminated, and Oasis Petroleum no longer owns any of the limited liability company interests of Bobcat DevCo or Beartooth DevCo. Redemption of Common Units from Oasis Petroleum. On June 29, 2021, the Partnership redeemed 3,623,188 common units from Oasis Petroleum for $87.0 million. The proceeds to redeem such common units from Oasis Petroleum were derived from the Equity Offering (defined in Note 10 – Partnership Equity and Distributions). As of September 30, 2021, Oasis Petroleum owns approximately 70% of the Partnership’s outstanding common units.

Accrued Liabilities

Accrued Liabilities	9 Months Ended
	Sep. 30, 2021
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued Liabilities Accrued liabilities consist of the following: September 30, 2021 December 31, 2020 (In thousands) Accrued capital costs $ 12,176 $ 3,200 Accrued operating expenses 9,113 8,204 Other accrued liabilities 13,001 6,527 Total accrued liabilities $ 34,290 $ 17,931

Property, Plant and Equipment

Property, Plant and Equipment	9 Months Ended
	Sep. 30, 2021
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment consists of the following: September 30, 2021 December 31, 2020 (In thousands) Pipelines $ 540,399 $ 532,546 Natural gas processing plants 304,885 301,820 Produced and flowback water facilities 124,531 123,047 Compressor stations 188,254 185,474 Other property and equipment 33,560 34,548 Construction in progress 18,677 3,384 Total property, plant and equipment 1,210,306 1,180,819 Less: accumulated depreciation, amortization and impairment (268,549) (240,877) Total property, plant and equipment, net $ 941,757 $ 939,942

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt Long-term debt consists of the following: September 30, 2021 December 31, 2020 (In thousands) Revolving Credit Facility $ 210,000 $ 450,000 8.00% senior unsecured notes due April 1, 2029 450,000 — Less: unamortized deferred financing costs on senior unsecured notes (9,610) — Total long-term debt $ 650,390 $ 450,000 Revolving Credit Facility The Partnership has a revolving credit facility among OMP Operating, as borrower, Wells Fargo Bank, N.A., as administrative agent and the lenders party thereto (as amended, the “Revolving Credit Facility”). On March 22, 2021, the Partnership entered into the Fourth Amendment to the Revolving Credit Facility (the “Fourth Amendment”) to, among other things, (i) provide for the occurrence of the transactions pursuant to the Simplification Transaction, (ii) amend the consolidated total leverage ratio financial covenant to no greater than 5.00 to 1.00, (iii) amend the consolidated senior secured leverage ratio to no greater than 3.00 to 1.00, (iv) amend the consolidated interest coverage ratio to no less than 2.50 to 1.00, (v) provide for the issuance of the Senior Notes (defined below), (vi) decrease the aggregate lender commitments to $450.0 million, (vii) increase pricing for credit and (viii) extend the maturity date from September 25, 2022 until at least September 30, 2024. In connection with the Fourth Amendment to the Revolving Credit Facility, the Partnership accelerated $1.1 million of unamortized deferred financing costs in the first quarter of 2021. Following the Fourth Amendment, the applicable margin for borrowings under the Revolving Credit Facility varies from (a) in the case of LIBOR loans (defined in the Revolving Credit Facility as Eurodollar Loans), 2.25% to 3.25%, and (b) in the case of domestic bank prime rate loans (defined in the Revolving Credit Facility as ABR Loans) or swingline loans, 1.25% to 2.25%. The unused portion of the Revolving Credit Facility is subject to a commitment fee ranging from 0.375% to 0.500%. At September 30, 2021, the aggregate amount of elected commitments under the Revolving Credit Facility was $450.0 million, and there were $210.0 million of borrowings outstanding and $5.5 million of outstanding letters of credit, resulting in an unused borrowing capacity of $234.5 million. For the three and nine months ended September 30, 2021, the weighted average interest rate incurred on borrowings under the Revolving Credit Facility was 2.5% and 2.4%, respectively. The fair value of the Revolving Credit Facility approximates its carrying value since borrowings under the Revolving Credit Facility bear interest at variable rates, which are tied to current market rates. The Revolving Credit Facility contains customary events of default, as well as cross-default provisions with other indebtedness of the Partnership and its restricted subsidiaries. If an event of default occurs and is continuing, the lenders may declare all amounts outstanding under the Revolving Credit Facility to be immediately due and payable. There are no cross-default provisions between the Revolving Credit Facility and the indebtedness of Oasis Petroleum and its restricted subsidiaries. The Partnership was in compliance with the covenants under the Revolving Credit Facility at September 30, 2021. Senior Unsecured Notes On March 30, 2021, the Partnership and OMP Finance Corp. (“OMP Finance” and together with the Partnership, the “Issuers”) issued in a private placement $450.0 million of 8.00% senior unsecured notes due April 1, 2029 (the “Senior Notes”). The Senior Notes were issued at par and resulted in net proceeds, after deducting the underwriters’ gross spread, of $442.1 million. The Partnership used the net proceeds from the Senior Notes to: (i) make a distribution to OMS of $231.5 million in connection with the Simplification Transaction, (ii) repay $204.0 million of outstanding principal borrowings and $0.5 million of accrued interest under the Revolving Credit Facility and (iii) pay approximately $6.1 million in fees and other expenses. In connection with the issuance of the Senior Notes, the Partnership recorded deferred financing costs of $10.2 million which are being amortized over the term of the Senior Notes. The fair value of the Senior Notes, which are publicly traded among qualified institutional investors and represent a Level 1 measurement, was $468.0 million at September 30, 2021. Interest on the Senior Notes is payable semi-annually on April 1 and October 1 of each year, commencing on October 1, 2021. The Senior Notes are fully and unconditionally guaranteed on a senior unsecured basis by the Issuers, along with the Partnership’s wholly-owned subsidiaries (the “Guarantors”). The Senior Notes guarantees are joint and several obligations of the Guarantors. The Issuers and Guarantors do not have any significant restrictions on the ability to obtain funds from its subsidiaries by dividend or loan. In addition, there are no restrictions on the subsidiaries to transfer funds, and as such, there are no restricted net assets to disclose. The indenture governing the Senior Notes contains certain covenants that, subject to certain exceptions and qualifications, among other things, limit the Partnership’s ability and the ability of its restricted subsidiaries to, among other things: (i) incur or guarantee additional indebtedness or issue certain redeemable or preferred equity, (ii) make certain investments, (iii) declare or

Inventory

Inventory	9 Months Ended
	Sep. 30, 2021
Inventory Disclosure [Abstract]
Inventory	InventoryInventory consists primarily of spare parts and equipment related to the Partnership’s midstream infrastructure. Inventory is stated at the lower of cost and net realizable value with cost determined on an average cost method. The Partnership assesses the carrying value of inventory and uses estimates and judgments when making any adjustments necessary to reduce the carrying value to net realizable value. The Partnership recorded a de minimis write-down of its inventory during the nine months ended September 30, 2021 and during the three and nine months ended September 30, 2020. The carrying value of the Partnership’s inventory was $5.8 million and $7.0 million at September 30, 2021 and December 31, 2020, respectively.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Partnership has various contractual obligations in the normal course of its operations. There have been no material changes to the Partnership’s commitments and contingencies from those disclosed in its 2020 Annual Report. Litigation. The Partnership is party to various legal and/or regulatory proceedings from time to time arising in the ordinary course of business. When the Partnership determines that a loss is probable of occurring and is reasonably estimable, the Partnership accrues an undiscounted liability for such contingencies based on its best estimate using information available at the time. The Partnership discloses contingencies where an adverse outcome may be material, or where in the judgment of management, the matter should otherwise be disclosed.

Partnership Equity and Distribu

Partnership Equity and Distributions	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Partnership Equity and Distributions	Partnership Equity and Distributions Equity offering. On June 29, 2021, the Partnership completed an underwritten public offering of 3,623,188 common units representing limited partnership interests at a price to the public of $24.00 per common unit (the “Equity Offering”) and received net proceeds of $87.0 million, after deducting underwriting discounts and commissions. The Partnership used the proceeds from the Equity Offering to fund the redemption of 3,623,188 common units held by Oasis Petroleum (see Note 4 – Transactions with Affiliates). Cash distributions. On October 25, 2021, the Board of Directors of the General Partner declared the quarterly cash distribution for the third quarter of 2021 of $0.56 per unit. This distribution will be payable on November 29, 2021 to unitholders of record as of November 15, 2021. The following table details the distributions paid in respect of each period in which the distributions were earned for the periods presented: Distributions Limited Partners General Partner Period Record Date Distribution Date Distribution per limited partner unit Common units Subordinated units IDRs (In thousands) Q4 2020 March 8, 2021 March 18, 2021 $ 0.54 $ 10,842 $ 7,425 $ 1,027 Q1 2021 May 17, 2021 May 27, 2021 0.55 26,745 — — Q2 2021 August 16, 2021 August 27, 2021 0.56 27,232 — — Subordinated unit conversion. On March 19, 2021, the first business day following the payment of the Partnership’s distribution for the fourth quarter of 2020, the subordination period under the partnership agreement terminated in accordance with the terms thereof, and the Partnership’s 13,750,000 subordinated units representing limited partner interests, all of which were held by OMS Holdings, automatically converted into common units on a one-to-one basis. Incentive distribution rights. All of the Partnership’s IDRs, all of which were held by the General Partner, were eliminated in connection with the Simplification Transaction. See Note 4 — Transactions with Affiliates.

Earnings (Loss) Per Limited Par

Earnings (Loss) Per Limited Partner Unit	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Earnings (Loss) Per Limited Partner Unit	Earnings (Loss) Per Limited Partner Unit Earnings (loss) per limited partner unit is computed by dividing the respective limited partners’ interest in earnings (loss) attributable to the Partnership by the weighted average number of common and subordinated units outstanding. For periods prior to the conversion of subordinated units and IDR Elimination, the Partnership had more than one class of participating securities and used the two-class method when calculating earnings (loss) per limited partner unit. The classes of participating securities include common units, subordinated units and IDRs. Diluted earnings (loss) per limited partner unit reflects the potential dilution that could occur if securities or agreements to issue common units, such as awards under the LTIP, were exercised, settled or converted into common units. When it is determined that potential common units should be included in diluted net income (loss) per limited partner unit calculation, the impact is reflected by applying the treasury stock method. There are no adjustments made to net income (loss) attributable to Oasis Midstream Partners LP in the calculation of diluted earnings (loss) per unit. For the three and nine months ended September 30, 2021 and 2020, the diluted earnings (loss) per share calculation excludes the anti-dilutive effect of unvested restricted unit awards. The following is a calculation of the basic and diluted weighted average units outstanding for the periods presented: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (In thousands) Basic weighted average common units outstanding 48,570 20,045 39,829 20,044 Dilutive effect of restricted awards 29 3 29 — Diluted weighted average common units outstanding 48,599 20,048 39,858 20,044 The following tables present the calculation of earnings (loss) per limited partner unit under the two-class method for each period presented (in thousands, except per unit data): Three Months Ended September 30, 2021 Net income attributable to Oasis Midstream Partners LP Distributions $ 27,232 Undistributed earnings attributable to Oasis Midstream Partners LP 10,388 Net income attributable to Oasis Midstream Partners LP $ 37,620 Weighted average limited partners units outstanding Common units – basic 48,570 Common units – diluted 48,599 Net income attributable to Oasis Midstream Partners LP per limited partner unit Basic $ 0.77 Diluted 0.77 Anti-dilutive restricted units 28 Three Months Ended September 30, 2020 General Partner Limited Partners IDRs Common units Subordinated units Total Net income attributable to Oasis Midstream Partners LP Distributions $ 1,027 $ 10,833 $ 7,425 $ 19,285 Undistributed earnings attributable to Oasis Midstream Partners LP — 4,730 3,246 7,976 Net income attributable to Oasis Midstream Partners LP $ 1,027 $ 15,563 $ 10,671 $ 27,261 Weighted average limited partners units outstanding Basic 20,045 Diluted 20,048 Net income attributable to Oasis Midstream Partners LP per limited partner unit Basic $ 0.78 Diluted 0.78 Anti-dilutive restricted units 13 Nine Months Ended September 30, 2021 Limited Partners Common units Subordinated units Total Net income attributable to Oasis Midstream Partners LP Distributions $ 64,819 $ 7,425 $ 72,244 Undistributed earnings attributable to Oasis Midstream Partners LP 24,058 2,373 26,431 Net income attributable to Oasis Midstream Partners LP $ 88,877 $ 9,798 $ 98,675 Weighted average limited partners units outstanding Basic 39,829 Diluted 39,858 Net income attributable to Oasis Midstream Partners LP per limited partner unit Basic $ 2.23 Diluted 2.23 Anti-dilutive restricted units 14 Nine Months Ended September 30, 2020 General Partner Limited Partners IDRs Common units Subordinated units Total Net income (loss) attributable to Oasis Midstream Partners LP Distributions $ 3,081 $ 32,499 $ 22,275 $ 57,855 Undistributed loss attributable to Oasis Midstream Partners LP — (53,452) (36,667) (90,119) Net income (loss) attributable to Oasis Midstream Partners LP $ 3,081 $ (20,953) $ (14,392) $ (32,264) Weighted average limited partners units outstanding Basic 20,044 Diluted 20,044 Net loss attributable to Oasis Midstream Partners LP per limited partner unit Basic $ (1.05) Diluted (1.05) Anti-dilutive restricted units 16

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On October 25, 2021, the Partnership and the General Partner entered into an Agreement and Plan of Merger (the “Merger Agreement”), with Crestwood Equity Partners LP, a Delaware limited partnership (“Crestwood”), Project Falcon Merger Sub LLC, a Delaware limited liability company and direct wholly-owned subsidiary of Crestwood (“Merger Sub”), Project Phantom Merger Sub LLC, a Delaware limited liability company and direct wholly-owned subsidiary of Crestwood (“GP Merger Sub”), and, solely for the purposes of Section 2.1(a)(i) of the Merger Agreement, Crestwood Equity GP LLC, a Delaware limited liability company and the general partner of Crestwood (“Crestwood GP”). Upon the terms and subject to the conditions set forth in the Merger Agreement, Merger Sub will merge with and into the Partnership (the “LP Merger”), with the Partnership surviving the LP Merger as a subsidiary of Crestwood, and GP Merger Sub will merge with and into the General Partner (the “GP Merger” and, together with the LP Merger, the “Mergers”), with the General Partner surviving the GP Merger as a wholly-owned subsidiary of Crestwood. On October 25, 2021, the board of directors of Crestwood GP, and the board of directors of the General Partner (“GP Board”), unanimously approved the Merger Agreement. The Conflicts Committee of the GP Board provided Special Approval (as defined in the Second Amended and Restated Agreement of Limited Partnership of the Partnership, dated as of March 30, 2021), and in connection with such Special Approval received a fairness opinion from Jefferies LLC. At the effective time of the Mergers (the “Effective Time”): (i) 6,520,944 common units representing limited partner interests in the Partnership (“Partnership Common Units”) issued and outstanding immediately prior to the Effective Time and owned by OMS Holdings (such Partnership Common Units, the “Sponsor Cash Units”), will be converted into and will thereafter represent the right to receive $150.0 million in cash in the aggregate and each other Partnership Common Unit issued and outstanding immediately prior to the Effective Time owned by Oasis Petroleum or its subsidiaries (other than the Partnership) (together with the Sponsor Cash Units, the “Sponsor Units”) will be converted into and will thereafter represent the right to receive 0.7680 common units representing limited partner interests in Crestwood (“Crestwood Common Units”); (ii) each Partnership Common Unit issued and outstanding immediately prior to the Effective Time (other than the Sponsor Units) will be converted into and will thereafter represent the right to receive 0.8700 (the “Public Holder Exchange Ratio”) Crestwood Common Units and (iii) all of the limited liability company interests of the General Partner issued and outstanding as of immediately prior to the Effective Time will be converted into and will thereafter represent the right to receive $10.0 million in cash. Upon completion of the Mergers, Oasis Petroleum is expected to own approximately 22% of the Crestwood Common Units. The Mergers are expected to close in the first quarter of 2022 and are subject to customary closing conditions, including regulatory approvals. Contemporaneously with the execution of the Merger Agreement, the Partnership, Crestwood, Oasis Petroleum, the General Partner and OMS Holdings entered into a support agreement (the “Support Agreement”) regarding the Partnership Common

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements of the Partnership have not been audited by the Partnership’s independent registered public accounting firm, except that the Condensed Consolidated Balance Sheet at December 31, 2020 is derived from audited financial statements. In the opinion of management, all adjustments, consisting of normal recurring adjustments necessary for fair statement of the Partnership’s financial position have been included. Management has made certain estimates and assumptions that affect reported amounts in the condensed consolidated financial statements and disclosures of contingencies. Actual results may differ from those estimates. The results for interim periods are not necessarily indicative of annual results. These interim financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Certain disclosures have been condensed or omitted from these financial statements. Accordingly, they do not include all of the information and notes required by accounting principles generally accepted in the United States of America (“GAAP”) for complete consolidated financial statements and should be read in conjunction with the Partnership’s audited consolidated financial statements and notes thereto included in the Partnership’s Annual Report on Form 10-K for the year ended December 31, 2020 (“2020 Annual Report”).
Simplification Transaction	Simplification Transaction On March 30, 2021, the Partnership closed the Simplification Transaction (defined below) with Oasis Petroleum to acquire Oasis Petroleum’s remaining ownership interests in Bobcat DevCo and Beartooth DevCo. In addition, the Simplification Transaction eliminated the incentive distribution rights (the “IDRs”) held by the General Partner (see Note 4 — Transactions with Affiliates). Prior to the Simplification Transaction, the Contributed Assets (defined below) were reflected as non-controlling interests in the Partnership’s unaudited condensed consolidated financial statements. In accordance with the Financial Accounting Standard Board’s (“FASB”) authoritative guidance under Accounting Standards Codification (“ASC”) Topic 810-10 for non-controlling interests in a common control transaction, the Partnership accounted for the Simplification Transaction as an equity transaction and adjusted the carrying amount of non-controlling interests in the condensed consolidated financial statements to reflect the change in ownership interests. Furthermore, as the Partnership acquired additional interests in previously consolidated subsidiaries, the Simplification Transaction did not result in a change in reporting entity, as defined under the FASB authoritative guidance under ASC Topic 805, Business Combinations , and was accounted for on a prospective basis.
Consolidation	Consolidation The Partnership’s condensed consolidated financial statements include its accounts and the accounts of the DevCos, each of which is a wholly-owned subsidiary of the Partnership and controlled by the Partnership through OMP GP LLC (the “General Partner”). All intercompany balances and transactions have been eliminated upon consolidation.
Risk and Uncertainties	Risks and Uncertainties Concentrations of market and credit risk. The Partnership has limited direct exposure to risks associated with fluctuating commodity prices due to the nature of its business and its long-term, fixed-fee contractual arrangements with its existing customers, including Oasis Petroleum. However, to the extent that the Partnership’s future contractual arrangements with customers, including Oasis Petroleum or third parties, do not provide for fixed-fee structures, the Partnership may become subject to more substantial direct commodity price risk. In addition, in response to a prolonged low commodity price environment, the Partnership’s customers could seek to amend existing contractual arrangements to reduce the volumetric fees the Partnership charges.
Significant Accounting Policies and Recent Accounting Pronouncements	Significant Accounting Policies There have been no material changes to the Partnership’s critical accounting policies and estimates from those disclosed in the 2020 Annual Report. Recent Accounting Pronouncements Reference rate reform. In March 2020, the FASB issued Accounting Standards Update 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting (“ASU 2020-04”). The amendments provide
Revenue Recognition	Prior Period Performance ObligationsThe Partnership records revenue when the performance obligations under the terms of its customer contracts are satisfied. The Partnership measures the satisfaction of its performance obligations using the output method based upon the volumes of crude oil, natural gas or water that flow through its systems. In certain cases, the Partnership is required to estimate these volumes during a reporting period and record any differences between the estimated volumes and actual volumes in the following reporting period. Such differences have historically not been significant.Contract BalancesContract balances are the result of timing differences between revenue recognition, billings and cash collections. Contract assets relate to revenue recognized for accrued deficiency fees associated with minimum volume commitments where the Partnership believes it is probable there will be a shortfall payment and that a significant reversal of revenue recognized will not occur once the related performance period is completed and the customer is billed. Contract liabilities relate to aid in construction payments received from customers, which are recognized as revenue over the expected period of future benefit. The Partnership does not recognize contract assets or contract liabilities under its customer contracts for which invoicing occurs once the Partnership’s performance obligations have been satisfied and payment is unconditional. Contract balances are classified as current or long-term based on the timing of when the Partnership expects to receive cash for contract assets or recognize revenue for contract liabilities. The Partnership has elected practical expedients, pursuant to ASC 606, Revenue from Contracts with Customers , to exclude from the presentation of remaining performance obligations: (i) contracts with index-based pricing or variable volume attributes in which such variable consideration is allocated entirely to a wholly unsatisfied performance obligation or to a wholly unsatisfied promise to transfer a distinct service that forms part of a series of distinct services and (ii) contracts with an original expected duration of one year or less.

Organization and Nature of Op_2

Organization and Nature of Operations (Tables)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Ownership Interests in DevCos	As of September 30, 2021, the Partnership’s assets in the DevCos were as follows: DevCo Areas Served Service Lines Bighorn DevCo Wild Basin – Natural gas processing – Crude oil terminaling – Crude oil transportation – Crude oil gathering Bobcat DevCo Wild Basin – Natural gas gathering – Natural gas compression – Gas lift supply – Crude oil gathering – Produced and flowback water gathering – Produced and flowback water disposal Beartooth DevCo Alger – Produced and flowback water gathering – Produced and flowback water disposal – Freshwater supply and distribution Panther DevCo Permian Basin – Crude oil gathering – Produced and flowback water gathering – Produced and flowback water disposal

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table presents revenues associated with contracts with customers for the periods presented: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (In thousands) Service revenues Crude oil, natural gas and NGL revenues $ 46,889 $ 43,137 $ 135,546 $ 138,226 Produced and flowback water revenues 24,466 26,217 70,124 79,155 Total service revenues 71,355 69,354 205,670 217,381 Product revenues Crude oil, natural gas and NGL revenues 32,187 13,863 88,378 31,165 Freshwater revenues 1,833 1,338 6,955 8,699 Total product revenues 34,020 15,201 95,333 39,864 Total revenues $ 105,375 $ 84,555 $ 301,003 $ 257,245
Changes in Contract Assets and Liabilities	The following table summarizes the changes in contract liabilities for the nine months ended September 30, 2021: (In thousands) Balance as of December 31, 2020 $ 5,421 Cash received 3,231 Revenue recognized (367) Balance as of September 30, 2021 $ 8,285
Estimated Timing of Remaining Performance Obligation	The following table presents estimated revenue allocated to remaining performance obligations for contracted revenues that are unsatisfied (or partially satisfied) as of September 30, 2021: (In thousands) 2021 (excluding nine months ended September 30, 2021) $ 3,709 2022 17,175 2023 10,896 2024 11,089 2025 2,768 Total $ 45,637

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	9 Months Ended
	Sep. 30, 2021
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued liabilities consist of the following: September 30, 2021 December 31, 2020 (In thousands) Accrued capital costs $ 12,176 $ 3,200 Accrued operating expenses 9,113 8,204 Other accrued liabilities 13,001 6,527 Total accrued liabilities $ 34,290 $ 17,931

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	9 Months Ended
	Sep. 30, 2021
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	Property, plant and equipment consists of the following: September 30, 2021 December 31, 2020 (In thousands) Pipelines $ 540,399 $ 532,546 Natural gas processing plants 304,885 301,820 Produced and flowback water facilities 124,531 123,047 Compressor stations 188,254 185,474 Other property and equipment 33,560 34,548 Construction in progress 18,677 3,384 Total property, plant and equipment 1,210,306 1,180,819 Less: accumulated depreciation, amortization and impairment (268,549) (240,877) Total property, plant and equipment, net $ 941,757 $ 939,942

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Schedule of Debt	Long-term debt consists of the following: September 30, 2021 December 31, 2020 (In thousands) Revolving Credit Facility $ 210,000 $ 450,000 8.00% senior unsecured notes due April 1, 2029 450,000 — Less: unamortized deferred financing costs on senior unsecured notes (9,610) — Total long-term debt $ 650,390 $ 450,000

Partnership Equity and Distri_2

Partnership Equity and Distributions (Tables)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Schedule of Percentage Allocations of Available Cash from Operating Surplus	The following table details the distributions paid in respect of each period in which the distributions were earned for the periods presented: Distributions Limited Partners General Partner Period Record Date Distribution Date Distribution per limited partner unit Common units Subordinated units IDRs (In thousands) Q4 2020 March 8, 2021 March 18, 2021 $ 0.54 $ 10,842 $ 7,425 $ 1,027 Q1 2021 May 17, 2021 May 27, 2021 0.55 26,745 — — Q2 2021 August 16, 2021 August 27, 2021 0.56 27,232 — —

Earnings (Loss) Per Limited P_2

Earnings (Loss) Per Limited Partner Unit (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Calculation of Basic and Diluted Weighted Average Number of Units Outstanding	The following is a calculation of the basic and diluted weighted average units outstanding for the periods presented: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 (In thousands) Basic weighted average common units outstanding 48,570 20,045 39,829 20,044 Dilutive effect of restricted awards 29 3 29 — Diluted weighted average common units outstanding 48,599 20,048 39,858 20,044
Schedule of Net Income per Limited Partner Unit	The following tables present the calculation of earnings (loss) per limited partner unit under the two-class method for each period presented (in thousands, except per unit data): Three Months Ended September 30, 2021 Net income attributable to Oasis Midstream Partners LP Distributions $ 27,232 Undistributed earnings attributable to Oasis Midstream Partners LP 10,388 Net income attributable to Oasis Midstream Partners LP $ 37,620 Weighted average limited partners units outstanding Common units – basic 48,570 Common units – diluted 48,599 Net income attributable to Oasis Midstream Partners LP per limited partner unit Basic $ 0.77 Diluted 0.77 Anti-dilutive restricted units 28 Three Months Ended September 30, 2020 General Partner Limited Partners IDRs Common units Subordinated units Total Net income attributable to Oasis Midstream Partners LP Distributions $ 1,027 $ 10,833 $ 7,425 $ 19,285 Undistributed earnings attributable to Oasis Midstream Partners LP — 4,730 3,246 7,976 Net income attributable to Oasis Midstream Partners LP $ 1,027 $ 15,563 $ 10,671 $ 27,261 Weighted average limited partners units outstanding Basic 20,045 Diluted 20,048 Net income attributable to Oasis Midstream Partners LP per limited partner unit Basic $ 0.78 Diluted 0.78 Anti-dilutive restricted units 13 Nine Months Ended September 30, 2021 Limited Partners Common units Subordinated units Total Net income attributable to Oasis Midstream Partners LP Distributions $ 64,819 $ 7,425 $ 72,244 Undistributed earnings attributable to Oasis Midstream Partners LP 24,058 2,373 26,431 Net income attributable to Oasis Midstream Partners LP $ 88,877 $ 9,798 $ 98,675 Weighted average limited partners units outstanding Basic 39,829 Diluted 39,858 Net income attributable to Oasis Midstream Partners LP per limited partner unit Basic $ 2.23 Diluted 2.23 Anti-dilutive restricted units 14 Nine Months Ended September 30, 2020 General Partner Limited Partners IDRs Common units Subordinated units Total Net income (loss) attributable to Oasis Midstream Partners LP Distributions $ 3,081 $ 32,499 $ 22,275 $ 57,855 Undistributed loss attributable to Oasis Midstream Partners LP — (53,452) (36,667) (90,119) Net income (loss) attributable to Oasis Midstream Partners LP $ 3,081 $ (20,953) $ (14,392) $ (32,264) Weighted average limited partners units outstanding Basic 20,044 Diluted 20,044 Net loss attributable to Oasis Midstream Partners LP per limited partner unit Basic $ (1.05) Diluted (1.05) Anti-dilutive restricted units 16

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Total revenues	$ 105,375	$ 84,555	$ 301,003	$ 257,245
Service revenues
Disaggregation of Revenue [Line Items]
Total revenues	71,355	69,354	205,670	217,381
Product revenues
Disaggregation of Revenue [Line Items]
Total revenues	34,020	15,201	95,333	39,864
Crude oil, natural gas and NGL revenues | Service revenues
Disaggregation of Revenue [Line Items]
Total revenues	46,889	43,137	135,546	138,226
Crude oil, natural gas and NGL revenues | Product revenues
Disaggregation of Revenue [Line Items]
Total revenues	32,187	13,863	88,378	31,165
Produced and flowback water revenues | Service revenues
Disaggregation of Revenue [Line Items]
Total revenues	24,466	26,217	70,124	79,155
Freshwater revenues | Product revenues
Disaggregation of Revenue [Line Items]
Total revenues	$ 1,833	$ 1,338	$ 6,955	$ 8,699

Revenue Recognition - Summary o

Revenue Recognition - Summary of Contract Assets and Contract Liabilities Activity (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Change in Contract with Customer, Liability [Abstract]
Balance as of December 31, 2020	$ 5,421
Cash received	3,231
Revenue recognized	(367)
Balance as of September 30, 2021	$ 8,285

Revenue Recognition - Estimated

Revenue Recognition - Estimated Timing of Remaining Performance Obligation (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 45,637
Timing of satisfaction of performance obligation	The partially and wholly unsatisfied performance obligations presented in the table above are generally limited to customer contracts which have fixed pricing and fixed volume terms and conditions, which generally include customer contracts with minimum volume commitment payment obligations.
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation period	3 months
Remaining performance obligation	$ 3,709
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation period	1 year
Remaining performance obligation	$ 17,175
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation period	1 year
Remaining performance obligation	$ 10,896
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation period	1 year
Remaining performance obligation	$ 11,089
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation period	1 year
Remaining performance obligation	$ 2,768

Transactions with Affiliates (D

Transactions with Affiliates (Details) - USD ($) $ in Thousands	Jun. 29, 2021	Mar. 30, 2021	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Related Party Transaction [Line Items]
Cash distributions, cash consideration		$ 229,000
Cash distributions, upward adjustment to purchase price		10,100
Cash distributions, downward adjustment to purchase price		$ 7,600
Units redeemed (in shares)	3,623,188
Redemption of common units	$ 87,000			$ 86,957
Public Stock Offering
Related Party Transaction [Line Items]
Sale of stock, number of shares issued in transaction (in shares)	3,623,188
Sale of stock, consideration received on transaction	$ 87,000
Bobcat DevCo | Oasis Midstream Partners, LP
Related Party Transaction [Line Items]
Percentage acquired		64.70%
Beartooth DevCo | Oasis Midstream Partners, LP
Related Party Transaction [Line Items]
Percentage acquired		30.00%
Oasis Midstream Partners, LP
Related Party Transaction [Line Items]
Ownership interest						70.00%
Commercial Agreements with OPNA, Oasis Petroleum Marketing LLC (“OPM”) and OMS | Oasis | Centralized Corporate, General and Administrative Services
Related Party Transaction [Line Items]
General and administrative			$ 5,600		$ 7,900	$ 19,500	$ 23,600
Simplification Transaction | Oasis
Related Party Transaction [Line Items]
Consideration contributed		$ 512,500
General partner cash distributions		$ 231,500
Limited partners ownership interest (in shares)		12,949,644
Convertible units, limited partners interest (in shares)		1,850,356

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Accrued capital costs	$ 12,176	$ 3,200
Accrued operating expenses	9,113	8,204
Other accrued liabilities	13,001	6,527
Total accrued liabilities	$ 34,290	$ 17,931

Property, Plant and Equipment_2

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 1,210,306	$ 1,180,819
Less: accumulated depreciation, amortization and impairment	(268,549)	(240,877)
Total property, plant and equipment, net	941,757	939,942
Pipelines
Property, Plant and Equipment [Line Items]
Property, plant and equipment	540,399	532,546
Natural gas processing plants
Property, Plant and Equipment [Line Items]
Property, plant and equipment	304,885	301,820
Produced and flowback water facilities
Property, Plant and Equipment [Line Items]
Property, plant and equipment	124,531	123,047
Compressor stations
Property, Plant and Equipment [Line Items]
Property, plant and equipment	188,254	185,474
Other property and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	33,560	34,548
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 18,677	$ 3,384

Long-Term Debt - Schedule of De

Long-Term Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Mar. 30, 2021	Dec. 31, 2020
Line of Credit Facility [Line Items]
Total long-term debt	$ 650,390		$ 450,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Long-term debt, gross	210,000		450,000
Senior Unsecured Notes
Line of Credit Facility [Line Items]
Long-term debt, gross	450,000	$ 450,000	0
Less: unamortized deferred financing costs on senior unsecured notes	$ (9,610)	$ (10,200)	$ 0
Debt instrument, interest rate		8.00%

Long-Term Debt - Revolving Cred

Long-Term Debt - Revolving Credit Facility (Details) - Revolving Credit Facility - USD ($) $ in Millions	Mar. 22, 2021	Sep. 30, 2021	Sep. 30, 2021
Line of Credit Facility [Line Items]
Debt obligations, maximum leverage ratio	500.00%
Debt obligation, maximum senior secured leverage ratio	300.00%
Debt obligation, maximum consolidated interest coverage ratio	250.00%
Decrease in aggregate lender commitments	$ 450
Accelerate deferred financing costs	$ 1.1
Maximum aggregate commitment amount		$ 450	$ 450
Line of credit outstanding		210	210
Letters of credit outstanding		5.5	5.5
Unused borrowing capacity		$ 234.5	$ 234.5
Weighted average interest rate (percent)		2.50%	2.40%
Minimum
Line of Credit Facility [Line Items]
Commitment fee rate (percent)			0.375%
Minimum | Eurodollar
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate (percent)			2.25%
Minimum | Alternate Based Rate (ABR)
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate (percent)			1.25%
Maximum
Line of Credit Facility [Line Items]
Commitment fee rate (percent)			0.50%
Maximum | Eurodollar
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate (percent)			3.25%
Maximum | Alternate Based Rate (ABR)
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate (percent)			2.25%

Long-Term Debt - Senior Unsecur

Long-Term Debt - Senior Unsecured Notes (Details) - USD ($) $ in Thousands	Mar. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Line of Credit Facility [Line Items]
Payments on revolving credit facility		$ 279,500	$ 0
Payments for other fees	$ 6,100
Simplification Transaction | Oasis
Line of Credit Facility [Line Items]
General partner cash distributions	231,500
Senior Unsecured Notes
Line of Credit Facility [Line Items]
Long-term debt, gross	$ 450,000	450,000		$ 0
Debt instrument, interest rate	8.00%
Proceeds from issuance of debt	$ 442,100
Deferred financing costs	10,200	9,610		0
Senior Unsecured Notes | Fair Value, Inputs, Level 1
Line of Credit Facility [Line Items]
Fair value of debt		468,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Long-term debt, gross		$ 210,000		$ 450,000
Payments on revolving credit facility	204,000
Repayments of line of credit, accrued interest	$ 500

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Inventory	$ 5,828	$ 6,986

Partnership Equity and Distri_3

Partnership Equity and Distributions - Percentage Allocations of Available Cash from Operating Surplus (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Distribution Made to Limited Partner [Line Items]
Distribution per limited partner unit (in dollars per share)	$ 0.56	$ 0.55	$ 0.54
General Partner
Distribution Made to Limited Partner [Line Items]
Cash distribution declared	$ 0	$ 0	$ 1,027
Common Units | Limited Partners
Distribution Made to Limited Partner [Line Items]
Cash distribution declared	27,232	26,745	10,842
Subordinated Units | Limited Partners
Distribution Made to Limited Partner [Line Items]
Cash distribution declared	$ 0	$ 0	$ 7,425

Partnership Equity and Distri_4

Partnership Equity and Distributions - Narrative (Details) $ / shares in Units, $ in Thousands	Oct. 25, 2021$ / shares	Jun. 29, 2021USD ($)$ / sharesshares	Mar. 30, 2021	Mar. 19, 2021shares	Jun. 30, 2021USD ($)$ / shares	Mar. 31, 2021$ / shares	Dec. 31, 2020$ / shares
Distribution Made to Limited Partner [Line Items]
Units redeemed (in shares) | shares		3,623,188
Redemption of common units | $		$ 87,000			$ 86,957
Distribution per limited partner unit (in dollars per share) | $ / shares					$ 0.56	$ 0.55	$ 0.54
Public Stock Offering
Distribution Made to Limited Partner [Line Items]
Sale of stock, number of shares issued in transaction (in shares) | shares		3,623,188
Sale of stock, price per share | $ / shares		$ 24
Sale of stock, consideration received on transaction | $		$ 87,000
Subsequent Event
Distribution Made to Limited Partner [Line Items]
Distribution per limited partner unit (in dollars per share) | $ / shares	$ 0.56
Bobcat DevCo | Oasis Midstream Partners, LP
Distribution Made to Limited Partner [Line Items]
Percentage acquired			64.70%
Beartooth DevCo | Oasis Midstream Partners, LP
Distribution Made to Limited Partner [Line Items]
Percentage acquired			30.00%
Subordinated Units
Distribution Made to Limited Partner [Line Items]
Convertible units, limited partners interest (in shares) | shares				13,750,000
Partners' capital account, units, conversion ratio				1

Earnings (Loss) Per Limited P_3

Earnings (Loss) Per Limited Partner Unit - Calculation of Basic and Diluted Weighted Average Number of Units Outstanding (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Basic weighted average common units outstanding (in shares)	48,570	20,045	39,829	20,044
Diluted weighted average common units outstanding (in shares)	48,599	20,048	39,858	20,044
Limited Partners
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Basic weighted average common units outstanding (in shares)	48,570	20,045	39,829	20,044
Dilutive effect of restricted awards (in shares)	29	3	29	0
Diluted weighted average common units outstanding (in shares)	48,599	20,048	39,858	20,044

Earnings (Loss) Per Limited P_4

Earnings (Loss) Per Limited Partner Unit - Net Income per Limited Partner Unit (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net income attributable to Oasis Midstream Partners LP
Distributions		$ 19,285	$ 72,244	$ 57,855
Undistributed earnings attributable to Oasis Midstream Partners LP		7,976	26,431	(90,119)
Net income attributable to Oasis Midstream Partners LP		$ 27,261	$ 98,675	$ (32,264)
Weighted average limited partners units outstanding
Common units - basic (in shares)	48,570	20,045	39,829	20,044
Common units - diluted (in shares)	48,599	20,048	39,858	20,044
Net loss attributable to Oasis Midstream Partners LP per limited partner unit
Diluted (in usd per share)	$ 0.77	$ 0.78	$ 2.23	$ (1.05)
General Partner
Net income attributable to Oasis Midstream Partners LP
Distributions		$ 1,027		$ 3,081
Undistributed earnings attributable to Oasis Midstream Partners LP		0		0
Net income attributable to Oasis Midstream Partners LP		$ 1,027		$ 3,081
Limited Partners
Weighted average limited partners units outstanding
Common units - basic (in shares)	48,570	20,045	39,829	20,044
Common units - diluted (in shares)	48,599	20,048	39,858	20,044
Net loss attributable to Oasis Midstream Partners LP per limited partner unit
Basic (in usd per share)	$ 0.77	$ 0.78	$ 2.23	$ (1.05)
Diluted (in usd per share)	$ 0.77		$ 2.23
Anti-dilutive restricted units (in shares)	28	13	14	16
Common Units | Limited Partners
Net income attributable to Oasis Midstream Partners LP
Distributions	$ 27,232	$ 10,833	$ 64,819	$ 32,499
Undistributed earnings attributable to Oasis Midstream Partners LP	10,388	4,730	24,058	(53,452)
Net income attributable to Oasis Midstream Partners LP	$ 37,620	15,563	88,877	(20,953)
Subordinated Units | Limited Partners
Net income attributable to Oasis Midstream Partners LP
Distributions		7,425	7,425	22,275
Undistributed earnings attributable to Oasis Midstream Partners LP		3,246	2,373	(36,667)
Net income attributable to Oasis Midstream Partners LP		$ 10,671	$ 9,798	$ (14,392)

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event - OMP Merger $ in Millions	Oct. 25, 2021USD ($)shares
Crestwood Equity Partners LP
Subsequent Event [Line Items]
Percentage of ownership after transaction	22.00%
Limited Partners | Crestwood Equity Partners LP
Subsequent Event [Line Items]
Units outstanding (in shares) | shares	6,520,944
Cash paid	$ 150
Business acquisition, common shares, conversion ratio	76.80%
General Partner | Crestwood Equity Partners LP
Subsequent Event [Line Items]
Cash paid	$ 10
Business acquisition, common shares, conversion ratio	87.00%