Chord Energy (CHRD) 10-Q 4 Nov 21 2021 Q3 Quarterly report Financial data

Cover

Cover - 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	1-34776
Entity Registrant Name	Oasis Petroleum Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	80-0554627
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 Stock
Trading Symbol	OAS
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	false
Entity Shell Company	false
Entity Bankruptcy Proceedings, Reporting Current	true
Entity Common Stock, Shares Outstanding		19,749,642
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001486159
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	$ 448,608	$ 15,856
Restricted cash	0	4,370
Accounts receivable, net	269,740	206,539
Inventory	28,309	33,929
Prepaid expenses	4,274	9,729
Derivative instruments	0	467
Other current assets	2,326	727
Total current assets	753,257	271,617
Property, plant and equipment
Oil and gas properties (successful efforts method)	733,585	810,328
Other property and equipment	962,174	935,950
Less: accumulated depreciation, depletion and amortization	(112,915)	(17,491)
Total property, plant and equipment, net	1,582,844	1,728,787
Restricted cash – non–current	400,000	0
Assets held for sale, net	0	5,500
Derivative instruments	39,717	0
Long-term inventory	17,510	14,522
Operating right-of-use assets	5,115	6,083
Intangible assets	41,624	43,667
Goodwill	70,534	70,534
Other assets	88,911	18,327
Total assets	2,999,512	2,159,037
Current liabilities
Accounts payable	5,522	3,242
Revenues and production taxes payable	232,217	146,497
Accrued liabilities	129,000	126,284
Accrued interest payable	26,361	980
Derivative instruments	266,337	56,944
Advances from joint interest partners	1,874	2,723
Current operating lease liabilities	1,914	2,607
Other current liabilities	1,859	1,954
Total current liabilities	665,084	341,231
Long-term debt	1,041,895	710,000
Deferred income taxes	984	984
Asset retirement obligations	45,974	46,363
Derivative instruments	142,516	37,614
Operating lease liabilities	1,706	2,362
Other liabilities	8,022	7,744
Total liabilities	1,906,181	1,146,298
Commitments and contingencies (Note 18)
Stockholders’ equity
Common stock, $0.01 par value: 60,000,000 shares authorized; 20,096,011 shares issued and 19,905,228 shares outstanding at September 30, 2021 and 20,093,017 shares issued and 20,093,017 shares outstanding at December 31, 2020	200	200
Treasury stock, at cost: 190,783 shares at September 30, 2021 and no shares at December 31, 2020	(14,560)	0
Additional paid-in capital	866,992	965,654
Retained earnings (accumulated deficit)	51,810	(49,912)
Oasis share of stockholders’ equity	904,442	915,942
Non-controlling interests	188,889	96,797
Total stockholders’ equity	1,093,331	1,012,739
Total liabilities and stockholders’ equity	$ 2,999,512	$ 2,159,037

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	60,000,000	60,000,000
Common stock, shares issued (in shares)	20,096,011	20,093,017
Common stock, shares outstanding (in shares)	19,905,228	20,093,017
Treasury stock, shares (in shares)	190,783	0

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	$ 402,039	$ 271,059	$ 1,150,558	$ 825,209
Operating expenses
Lease operating expenses	29,307	29,353	98,888	108,730
Gathering, processing and transportation expenses	16,400	20,328	52,596	73,557
Production taxes	18,445	13,039	50,933	39,129
Depreciation, depletion and amortization	33,623	36,000	112,581	272,885
Exploration expenses	263	725	1,936	3,061
Rig termination	0	1,017	0	1,279
Impairment	0	2,578	5	4,828,575
General and administrative expenses	19,514	49,251	60,461	117,868
Litigation settlement	0	22,750	0	22,750
Total operating expenses	203,854	234,008	649,033	5,672,089
Gain on sale of properties	5,405	1,473	228,473	11,652
Operating income (loss)	203,590	38,524	729,998	(4,835,228)
Other income (expense)
Net gain (loss) on derivative instruments	(101,790)	(5,071)	(550,342)	243,064
Interest expense, net of capitalized interest	(18,153)	(37,389)	(49,421)	(177,534)
Gain (loss) on extinguishment of debt	0	(20)	0	83,867
Reorganization items, net	0	(49,758)	0	(49,758)
Other income (expense)	(315)	1,473	(859)	2,373
Total other income (expense), net	(120,258)	(90,765)	(600,622)	102,012
Income (loss) before income taxes	83,332	(52,241)	129,376	(4,733,216)
Income tax benefit	0	5,144	0	262,495
Net income (loss) including non-controlling interests	83,332	(47,097)	129,376	(4,470,721)
Less: Net income (loss) attributable to non-controlling interests	11,382	8,602	27,654	(11,218)
Net income (loss) attributable to Oasis	$ 71,950	$ (55,699)	$ 101,722	$ (4,459,503)
Earnings (loss) attributable to Oasis per share:
Basic (in dollars per share)	$ 3.63	$ (0.17)	$ 5.11	$ (14.05)
Diluted (in dollars per share)	$ 3.46	$ (0.17)	$ 4.96	$ (14.05)
Weighted average shares outstanding:
Basic (in shares)	19,812	318,287	19,905	317,365
Diluted (in shares)	20,786	318,287	20,508	317,365
Oil and Gas Services
Revenues
Total revenues	$ 281,636	$ 179,577	$ 782,324	$ 512,535
Purchased Oil and Gas
Revenues
Total revenues	53,570	44,194	183,885	167,824
Operating expenses
Expenses	53,880	47,549	187,745	165,932
Midstream Total
Revenues
Total revenues	66,712	46,979	183,807	138,164
Operating expenses
Expenses	32,396	11,110	83,841	32,355
Other Services
Revenues
Total revenues	121	309	542	6,686
Operating expenses
Expenses	$ 26	$ 308	$ 47	$ 5,968

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Changes in Stockholders' Equity (Deficit) (Unaudited) - USD ($) $ in Thousands	Total	Regular Cash Dividend	Special Cash Dividend	Cumulative effect adjustment	Common Stock	Treasury Stock	Additional Paid-in Capital	Additional Paid-in CapitalRegular Cash Dividend	Additional Paid-in CapitalSpecial Cash Dividend	Retained Earnings (Accumulated Deficit)	Retained Earnings (Accumulated Deficit)Cumulative effect adjustment	Non-controlling Interests
Balance (in shares) at Dec. 31, 2019					321,231,000	2,967,000
Balance at Dec. 31, 2019	$ 3,837,081			$ (410)	$ 3,189	$ (33,881)	$ 3,112,384			$ 554,446	$ (410)	$ 200,943
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation (in shares)					3,836,000
Equity-based compensation	7,105				$ 32		7,007					66
Distributions to non-controlling interest owners	(6,028)											(6,028)
Equity component of senior unsecured convertible notes, net	(337)						(337)
Treasury stock - tax withholdings (in shares)					942,000	942,000
Treasury stock - tax withholdings	(2,308)					$ (2,308)
Net income (loss)	(4,334,275)									(4,310,861)		(23,414)
Balance (in shares) at Mar. 31, 2020					324,125,000	3,909,000
Balance at Mar. 31, 2020	(499,172)				$ 3,221	$ (36,189)	3,119,054			(3,756,825)		171,567
Balance (in shares) at Dec. 31, 2019					321,231,000	2,967,000
Balance at Dec. 31, 2019	3,837,081			$ (410)	$ 3,189	$ (33,881)	3,112,384			554,446	$ (410)	200,943
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(4,470,721)
Balance (in shares) at Sep. 30, 2020					320,931,000	4,196,000
Balance at Sep. 30, 2020	(638,151)				$ 3,232	$ (36,532)	3,128,752			(3,905,467)		171,864
Balance (in shares) at Mar. 31, 2020					324,125,000	3,909,000
Balance at Mar. 31, 2020	(499,172)				$ 3,221	$ (36,189)	3,119,054			(3,756,825)		171,567
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation (in shares)					(2,889,000)
Equity-based compensation	4,942				$ 1,018		3,858					66
Distributions to non-controlling interest owners	(6,014)											(6,014)
Treasury stock - tax withholdings (in shares)					252,000	252,000
Treasury stock - tax withholdings	(318)					$ (318)
Net income (loss)	(89,349)									(92,943)		3,594
Balance (in shares) at Jun. 30, 2020					320,984,000	4,161,000
Balance at Jun. 30, 2020	(589,911)				$ 4,239	$ (36,507)	3,122,912			(3,849,768)		169,213
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation (in shares)					(18,000)
Equity-based compensation	4,902				$ (1,007)		5,840					69
Distributions to non-controlling interest owners	(6,020)											(6,020)
Treasury stock - tax withholdings (in shares)					35,000	35,000
Treasury stock - tax withholdings	(25)					$ (25)
Net income (loss)	(47,097)									(55,699)		8,602
Balance (in shares) at Sep. 30, 2020					320,931,000	4,196,000
Balance at Sep. 30, 2020	(638,151)				$ 3,232	$ (36,532)	3,128,752			(3,905,467)		171,864
Balance (in shares) at Dec. 31, 2020					20,093,000	0
Balance at Dec. 31, 2020	1,012,739				$ 200	$ 0	965,654			(49,912)		96,797
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	2,198						1,709					489
Dividends to shareholders		$ (7,535)						$ (7,535)
Distributions to non-controlling interest owners	(6,029)											(6,029)
Midstream Simplification (Note 2)	0						2,358					(2,358)
Common control transaction costs	(4,111)						(4,111)
Warrants exercised	6						6
Net income (loss)	(35,265)									(43,592)		8,327
Balance (in shares) at Mar. 31, 2021					20,093,000	0
Balance at Mar. 31, 2021	962,003				$ 200	$ 0	958,081			(93,504)		97,226
Balance (in shares) at Dec. 31, 2020					20,093,000	0
Balance at Dec. 31, 2020	$ 1,012,739				$ 200	$ 0	965,654			(49,912)		96,797
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Warrants exercised (in shares)	6,050
Repurchase of common stock (in shares)	(190,783)
Repurchase of common stock	$ (14,600)
Net income (loss)	129,376
Balance (in shares) at Sep. 30, 2021					19,905,000	191,000
Balance at Sep. 30, 2021	1,093,331				$ 200	$ (14,560)	866,992			51,810		188,889
Balance (in shares) at Mar. 31, 2021					20,093,000	0
Balance at Mar. 31, 2021	962,003				$ 200	$ 0	958,081			(93,504)		97,226
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	4,702						4,688					14
Dividends to shareholders		$ (8,090)	$ (82,958)					(8,090)	$ (82,958)
Distributions to non-controlling interest owners	(6,136)											(6,136)
Common control transaction costs	(1,321)						(1,321)
Warrants exercised (in shares)					2,000
Warrants exercised	167						167
Repurchase of common stock (in shares)					(191,000)	(191,000)
Repurchase of common stock	(14,560)					$ 14,560
Issuance of OMP common units, net of offering costs	86,657											86,657
Net income (loss)	81,309									73,364		7,945
Balance (in shares) at Jun. 30, 2021					19,904,000	191,000
Balance at Jun. 30, 2021	1,021,773				$ 200	$ (14,560)	870,567			(20,140)		185,706
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	4,287						4,143					144
Dividends to shareholders	(7,765)							$ (7,765)
Distributions to non-controlling interest owners	(8,278)											(8,278)
Common control transaction costs	$ (21)						(21)
Warrants exercised (in shares)	2,791				1,000
Warrants exercised	$ 68						68
Other	(65)											(65)
Net income (loss)	83,332									71,950		11,382
Balance (in shares) at Sep. 30, 2021					19,905,000	191,000
Balance at Sep. 30, 2021	$ 1,093,331				$ 200	$ (14,560)	$ 866,992			$ 51,810		$ 188,889

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Changes in Stockholders' Equity (Deficit) (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Sep. 30, 2021	Mar. 31, 2021
Regular Cash Dividend
Dividends to shareholders (in usd per share)	$ 0.375	$ 0.375

Condensed Consolidated Statem_4

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) including non-controlling interests	$ 129,376	$ (4,470,721)
Adjustments to reconcile net income (loss) including non-controlling interests to net cash provided by operating activities:
Depreciation, depletion and amortization	112,581	272,885
Gain on extinguishment of debt	0	(83,867)
Gain on sale of properties	(228,473)	(11,652)
Impairment	5	4,828,575
Deferred income taxes	0	(262,459)
Derivative instruments	550,342	(243,064)
Equity-based compensation expenses	11,187	16,531
Non-cash reorganization items, net	0	49,758
Deferred financing costs amortization and other	18,811	19,041
Working capital and other changes:
Change in accounts receivable, net	(65,324)	168,749
Change in inventory	2,408	(6,206)
Change in prepaid expenses	4,509	(6,107)
Change in accounts payable, interest payable and accrued liabilities	118,942	(112,479)
Change in other assets and liabilities, net	(9,618)	(4,079)
Net cash provided by operating activities	644,746	154,905
Cash flows from investing activities:
Capital expenditures	(143,201)	(291,776)
Acquisition deposit	(74,500)	0
Proceeds from sale of properties	373,892	15,188
Costs related to sale of properties	(2,785)	0
Derivative settlements	(160,018)	224,223
Derivative modification	(82,419)	0
Net cash used in investing activities	(89,031)	(52,365)
Cash flows from financing activities:
Proceeds from revolving credit facilities	384,500	967,189
Principal payments on revolving credit facilities	(884,500)	(914,549)
Proceeds from issuance of senior unsecured notes	850,000	0
Repurchase of senior unsecured notes	0	(68,060)
Deferred financing costs	(20,480)	(172)
Proceeds from issuance of OMP common units, net of offering costs	86,592	0
Common control transaction costs	(5,453)	0
Purchases of treasury stock	(14,560)	(2,651)
Dividends paid	(102,123)	0
Distributions to non-controlling interests	(20,443)	(18,062)
Payments on finance lease liabilities	(1,107)	(1,989)
Proceeds from warrants exercised	241	0
Net cash provided by (used in) financing activities	272,667	(38,294)
Increase in cash, cash equivalents and restricted cash	828,382	64,246
Cash, cash equivalents and restricted cash:
Beginning of period	20,226	20,019
End of period	848,608	84,265
Supplemental non-cash transactions:
Change in accrued capital expenditures	13,014	(81,939)
Change in asset retirement obligations	(389)	2,860
Note receivable from divestiture	2,900	0
Contingent consideration from Permian Basin Sale	$ 32,860	$ 0

Organization and Operations of

Organization and Operations of the Company	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Operations of the Company	Organization and Operations of the CompanyOasis Petroleum Inc. (together with its consolidated subsidiaries, “Oasis” or the “Company”) is an independent exploration and production (“E&P”) company focused on the acquisition and development of onshore, unconventional crude oil and natural gas resources in the United States. Oasis Petroleum North America LLC (“OPNA”) conducts the Company’s E&P activities and owns its oil and gas properties located in the North Dakota and Montana regions of the Williston Basin. During the second quarter of 2021, the Company sold its E&P assets in the Texas region of the Permian Basin (see Note 10 — Divestitures). In addition to its E&P segment, the Company operates a midstream business segment through Oasis Midstream Partners LP (“OMP”), a gathering and processing master limited partnership that owns, develops, operates and acquires a diversified portfolio of midstream assets in North America.

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 unaudited condensed consolidated financial statements of the Company have not been audited by the Company’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 the fair statement of the Company’s financial position, have been included. Management has made certain estimates and assumptions that affect reported amounts in the unaudited 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 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 Company’s audited consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 (“2020 Annual Report”). Consolidation. The accompanying unaudited condensed consolidated financial statements of the Company include the accounts of Oasis, its wholly-owned subsidiaries and OMP. The Company has determined that the partners with equity at risk in OMP lack the authority, through voting rights or similar rights, to direct the activities that most significantly impact OMP’s economic performance. Therefore, as the limited partners of OMP do not have substantive kick-out or substantive participating rights over its general partner, OMP GP LLC (“OMP GP”), OMP is a variable interest entity. Through the Company’s ownership of OMP GP, the Company has the authority to direct the activities that most significantly affect economic performance and the right to receive benefits that could be potentially significant to OMP. Therefore, the Company is the primary beneficiary and consolidates OMP. The Company records a non-controlling interest for the ownership interest held by public unitholders in OMP. As of September 30, 2021, Oasis owns approximately 70% of OMP. All intercompany balances and transactions have been eliminated upon consolidation. Midstream Simplification. On March 30, 2021, the Company completed the transactions contemplated by a contribution and simplification agreement (the “Contribution and Simplification Agreement”), dated as of March 22, 2021. Pursuant to the Contribution and Simplification Agreement, among other things, (a) the Company contributed to OMP its remaining limited liability company interests in Bobcat DevCo LLC (“Bobcat DevCo”) and Beartooth DevCo LLC (“Beartooth DevCo”) of 64.7% and 30.0%, respectively, in exchange for total consideration of approximately $512.5 million composed of (x) a cash distribution of $231.5 million and (y) 12,949,644 common units representing limited partner interests in OMP, (b) OMP’s incentive distribution rights were cancelled and converted into 1,850,356 OMP common units (the “IDR Conversion Common Units”), and (c) OMP GP distributed the IDR Conversion Common Units on a pro rata basis to holders of its Class A Units and Class B Units, such that following such distribution, Oasis, through its wholly-owned subsidiary OMS Holdings LLC (“OMS Holdings”), is the sole member of OMP GP (the foregoing clauses (a), (b) and (c), the “Midstream Simplification”). The effective date of the Midstream Simplification was January 1, 2021. Fresh start accounting. On November 19, 2020 (the “Emergence Date”), the Company emerged from bankruptcy and adopted fresh start accounting in accordance with the Financial Accounting Standards Board’s (“FASB”) Accounting Standards Codification 852, Reorganizations , which resulted in a new basis of accounting and the Company becoming a new entity for financial reporting purposes. As a result of the adoption of fresh start accounting, the condensed consolidated financial statements after the Emergence Date are not comparable to the condensed consolidated financial statements prior to that date. References to “Successor” relate to the reorganized Company’s financial position and results of operations as of and subsequent to the Emergence Date. References to “Predecessor” relate to the Company’s financial position prior to, and results of operations through and including, the Emergence Date. Risks and Uncertainties As a crude oil and natural gas producer, the Company’s revenue, profitability and future growth are substantially dependent upon the prevailing and future prices for crude oil and natural gas, which are dependent upon numerous factors beyond its control such as economic, political and regulatory developments and competition from other energy sources. The energy markets have historically been very volatile, and there can be no assurance that crude oil and natural gas prices will not be subject to wide fluctuations in the future. A substantial or extended decline in prices for crude oil and, to a lesser extent, natural gas and natural gas liquids (“NGLs”), could have a material adverse effect on the Company’s financial position, results of operations, cash flows, the quantities of crude oil and natural gas reserves that may be economically produced and the Company’s access to capital. Cash Equivalents and Restricted Cash The Company may invest in certain money market funds, commercial paper and time deposits, all of which are stated at fair value or cost which approximates fair value due to the short-term maturity of these investments. The Company classifies all such investments with original maturity dates less than 90 days as cash equivalents. As of September 30, 2021, restricted cash consisted of proceeds from the Oasis Senior Notes (defined in Note 11 – Long-Term Debt) held in a standalone account to fund a portion of the Williston Basin Acquisition (defined in Note 9 – Acquisitions). As of December 31, 2020, restricted cash consisted of funds that were held in an escrow account for the payment of professional fees associated with the Company’s emergence from bankruptcy. The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Condensed Consolidated Balance Sheets and Condensed Consolidated Statements of Cash Flows: Successor September 30, 2021 December 31, 2020 (In thousands) Cash and cash equivalents $ 448,608 $ 15,856 Restricted cash — 4,370 Restricted cash – non–current 400,000 — Total cash, cash equivalents and restricted cash $ 848,608 $ 20,226 Significant Accounting Policies There have been no material changes to the Company’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”). ASU 2020-04 provides optional guidance for a limited time to ease the potential burden in accounting for reference rate reform, including optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. ASU 2020-04 applies only to contracts and hedging relationships that reference the London Interbank Offered Rate (“LIBOR”) or another reference rate expected to be discontinued due to reference rate reform. ASU 2020-04 is effective immediately and may be applied prospectively to contract modifications made and hedging relationships entered into or evaluated on or before December 31, 2022. The Company is currently evaluating its contracts and the optional expedients provided by ASU 2020-04 and the impact the new standard will have on its financial statements and related disclosures.

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition Exploration and Production Revenues E&P revenues from contracts with customers for crude oil, natural gas and NGL sales and other services were as follows for the periods presented (in thousands): Successor Predecessor Successor Predecessor Three Months Ended September 30, 2021 Three Months Ended September 30, 2020 Nine Months Ended September 30, 2021 Nine Months Ended September 30, 2020 Crude oil revenues $ 205,731 $ 155,052 $ 598,278 $ 448,904 Purchased crude oil sales 53,562 35,442 163,785 144,719 Natural gas revenues 75,905 24,525 184,046 63,631 Purchased natural gas sales 8 308 362 4,909 Other services revenues 121 309 542 6,686 Total E&P revenues $ 335,327 $ 215,636 $ 947,013 $ 668,849 Midstream Revenues Midstream revenues are derived from contracts with customers for midstream services under fee-based arrangements and midstream product sales from purchase arrangements. The Company’s midstream revenues exclude intercompany revenues for goods and services provided by the midstream business segment for the Company’s ownership interests, which are eliminated in consolidation. Revenues derived from contracts with customers for midstream revenues were as follows for the periods presented (in thousands): Successor Predecessor Successor Predecessor Three Months Ended September 30, 2021 Three Months Ended September 30, 2020 Nine Months Ended September 30, 2021 Nine Months Ended September 30, 2020 Midstream service revenues Crude oil, natural gas and NGL revenues $ 22,111 $ 22,682 $ 65,225 $ 72,267 Produced and flowback water revenues 10,312 8,801 25,230 27,300 Total midstream service revenues 32,423 31,483 90,455 99,567 Midstream product revenues Purchased crude oil sales (1) — 8,444 $ 19,738 $ 18,196 Crude oil, natural gas and NGL revenues 33,845 15,100 91,671 35,707 Freshwater revenues 444 396 1,681 2,890 Total midstream product revenues 34,289 23,940 113,090 56,793 Total midstream revenues $ 66,712 $ 55,423 $ 203,545 $ 156,360 ___________________ (1) Reported under purchased oil and gas sales on the Condensed Consolidated Statements of Operations. 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 Company 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 Company does not recognize contract assets or contract liabilities under its customer contracts for which invoicing occurs once the Company’s performance obligations have been satisfied and payment is unconditional. Contract balances are classified as current or long-term based on when the Company expects to receive cash for contract assets or recognize revenue for contract liabilities. Contract liabilities are included in other current liabilities and other liabilities on the Company’s Condensed Consolidated Balance Sheets. There were no material contract asset balances at September 30, 2021 or December 31, 2020. The following table summarizes the changes in the Company’s contract liabilities for the nine months ended September 30, 2021: (In thousands) Balance as of December 31, 2020 (Successor) $ 3,966 Cash received 3,231 Revenues recognized (276) Balance as of September 30, 2021 (Successor) $ 6,921 Performance Obligations The Company records revenue when the performance obligations under the terms of its customer contracts are satisfied. For sales of commodities, the Company records revenue in the month the production or purchased product is delivered to the purchaser. However, settlement statements and payments are typically not received for 20 to 60 days after the date production is delivered, and as a result, the Company is required to estimate the amount of production that was delivered to the purchaser and the price that will be received for the sale of the product. The Company uses knowledge of its properties, its properties’ historical performance, spot market prices and other factors as the basis for these estimates. The Company records the differences between estimates and the actual amounts received for product sales once payment is received from the purchaser. For midstream services, the Company measures the satisfaction of its performance obligations using the output method based upon the volume of crude oil, natural gas or water that flows through its systems. In certain cases, the Company 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. Differences between estimated and actual revenues have historically not been significant. For the three and nine months ended September 30, 2021 and 2020, revenue recognized related to performance obligations satisfied in prior reporting periods was not material. 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 (Successor): (In thousands) 2021 (excluding the 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 Company has elected practical expedients, pursuant to Accounting Standards Codification 606, Revenue from Contracts with Customers

Inventory

Inventory	9 Months Ended
	Sep. 30, 2021
Inventory Disclosure [Abstract]
Inventory	Inventory The Company’s inventory includes equipment and materials and crude oil inventory. Equipment and materials consist primarily of well equipment, tanks and tubular goods to be used in the Company’s E&P activities and spare parts and equipment for the Company’s midstream assets. Crude oil inventory includes crude oil in tanks and linefill that is expected to be withdrawn within one year. Linefill represents the minimum volume of product in a pipeline system that enables the system to operate and is generally not available to be withdrawn from the pipeline system until the expiration of the transportation contract. Crude oil and NGL linefill in third-party pipelines that is not expected to be withdrawn within one year is included in long-term inventory on the Company’s Condensed Consolidated Balance Sheets. Inventory, including long-term inventory, is stated at the lower of cost and net realizable value with cost determined on an average cost method. The Company assesses the carrying value of inventory and uses estimates and judgment when making any adjustments necessary to reduce the carrying value to net realizable value. Among the uncertainties that impact the Company’s estimates are the applicable quality and location differentials to include in the Company’s net realizable value analysis as well as the liquidation timing of the inventory. Changes in assumptions made as to the timing of a sale can materially impact net realizable value. No material write-downs of inventory or long-term inventory were recorded during the three or nine months ended September 30, 2021. There were no write-downs of crude oil inventory or long-term inventory recorded during the three months ended September 30, 2020 (Predecessor). During the nine months ended September 30, 2020 (Predecessor), as a result of lower commodity prices, the Company recorded impairment losses related to the Company’s crude oil inventory and long-term linefill of $7.2 million and $1.3 million, respectively. In addition, during the three and nine months ended September 30, 2020, the Company recorded impairment charges of $0.6 million and $1.6 million, respectively, to write down the carrying value of certain equipment and materials inventory to the estimated net realizable value. The Company’s total inventory consists of the following: Successor September 30, 2021 December 31, 2020 (In thousands) Inventory Equipment and materials $ 19,563 $ 25,103 Crude oil inventory 8,746 8,826 Total inventory 28,309 33,929 Long-term inventory Linefill in third party pipelines 17,510 14,522 Total long-term inventory 17,510 14,522 Total $ 45,819 $ 48,451

Additional Balance Sheet Inform

Additional Balance Sheet Information	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Additional Balance Sheet Information	Additional Balance Sheet Information The following table sets forth certain balance sheet amounts comprised of the following: Successor September 30, 2021 December 31, 2020 (In thousands) Accounts receivable, net Trade accounts $ 200,301 $ 161,519 Joint interest accounts 39,291 31,920 Other accounts 31,560 13,206 Total accounts receivable 271,152 206,645 Less: allowance for credit losses (1,412) (106) Total accounts receivable, net $ 269,740 $ 206,539 Accrued liabilities Accrued capital costs $ 51,086 $ 39,380 Accrued lease operating expenses 15,257 18,635 Accrued oil and gas purchases 10,467 8,967 Accrued general and administrative expenses 9,964 35,249 Accrued dividends payable 4,224 — Accrued midstream operating expenses 21,933 15,051 Other accrued liabilities 16,069 9,002 Total accrued liabilities $ 129,000 $ 126,284

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value MeasurementsIn accordance with the FASB’s authoritative guidance on fair value measurements, the Company’s financial assets and liabilities are measured at fair value on a recurring basis. The Company’s financial instruments, including certain cash and cash equivalents, accounts receivable, accounts payable and other payables, are carried at cost, which approximates their respective fair market values due to their short-term maturities. The Company recognizes its non-financial assets and liabilities, such as asset retirement obligations (“ARO”) and properties acquired in a business combination or upon impairment, at fair value on a non-recurring basis. As defined in the authoritative guidance, fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). To estimate fair value, the Company utilizes market data or assumptions that market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs can be readily observable, market corroborated or generally unobservable. The authoritative guidance establishes a fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (“Level 1” measurements) and the lowest priority to unobservable inputs (“Level 3” measurements). The three levels of the fair value hierarchy are as follows: Level 1 — Unadjusted quoted prices are available in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2 — Pricing inputs, other than unadjusted quoted prices in active markets included in Level 1, are either directly or indirectly observable as of the reporting date. Level 2 includes those financial instruments that are valued using models or other valuation methodologies. These models are primarily industry-standard models that consider various assumptions, including quoted forward prices for commodities, time value, volatility factors and current market and contractual prices for the underlying instruments, as well as other relevant economic measures. Substantially all of these assumptions are observable in the marketplace throughout the full term of the instrument and can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace. Level 3 — Pricing inputs are generally unobservable from objective sources, requiring internally developed valuation methodologies that result in management’s best estimate of fair value. Financial Assets and Liabilities Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input requires judgment and may affect the valuation of fair value assets and liabilities and their placement within the fair value hierarchy levels. The following tables set forth by level, within the fair value hierarchy, the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis: Successor Fair value at September 30, 2021 Level 1 Level 2 Level 3 Total (In thousands) Assets: Permian Basin Sale Contingent Consideration $ — $ 39,717 $ — $ 39,717 Total assets $ — $ 39,717 $ — $ 39,717 Liabilities: Commodity derivative instruments $ — $ 408,853 $ — $ 408,853 Total liabilities $ — $ 408,853 $ — $ 408,853 Successor Fair value at December 31, 2020 Level 1 Level 2 Level 3 Total (In thousands) Assets: Commodity derivative instruments $ — $ 467 $ — $ 467 Total assets $ — $ 467 $ — $ 467 Liabilities: Commodity derivative instruments $ — $ 94,558 $ — $ 94,558 Total liabilities $ — $ 94,558 $ — $ 94,558 Commodity derivative instruments . The fair value of the Company’s commodity derivative instruments is based upon a third-party preparer’s calculation using mark-to-market valuation reports provided by the Company’s counterparties for monthly settlement purposes to determine the valuation of its derivative instruments. The Company has the third-party preparer evaluate other readily available market prices for its derivative contracts, as there is an active market for these contracts. The third-party preparer performs its independent valuation using a moment matching method similar to Turnbull-Wakeman for Asian options. The significant inputs used are commodity prices, volatility, skew, discount rate and the contract terms of the derivative instruments. The Company does not have access to the specific proprietary valuation models or inputs used by its counterparties or the third-party preparer. The Company compares the third-party preparer’s valuation to counterparty valuation statements, investigating any significant differences, and analyzes monthly valuation changes in relation to movements in forward commodity price curves. The determination of the fair value for derivative instruments also incorporates a credit adjustment for non-performance risk, as required by GAAP. The Company calculates the credit adjustment for derivatives in a net asset position using current credit default swap values for each counterparty. The credit adjustment for derivatives in a net liability position is based on the market credit spread of the Company or similarly rated public issuers. The Company recorded an adjustment to reduce the fair value of its net derivative liability by $8.7 million and $4.3 million at September 30, 2021 and December 31, 2020, respectively. See Note 7 – Derivative Instruments for more information. Permian Basin Sale Contingent Consideration. The fair value of the Permian Basin Sale Contingent Consideration (defined in Note 7 – Derivative Instruments) was determined by a third-party valuation specialist as of the close date using a Monte Carlo simulation model and Ornstein-Uhlenbeck pricing process. The significant inputs include NYMEX West Texas Intermediate crude oil price index (“NYMEX WTI”) forward price curve, volatility, mean reversion rate and counterparty credit risk adjustment. The Company determined these were Level 2 fair value inputs that are substantially observable in active markets or can be derived from observable data. See Note 7 – Derivative Instruments and Note 10 – Divestitures for more information. Non-Financial Assets and Liabilities The fair value of the Company’s non-financial assets measured at fair value on a non-recurring basis is determined using valuation techniques that include Level 3 inputs. Asset retirement obligations. The initial measurement of ARO at fair value is recorded in the period in which the liability is incurred. Fair value is determined by calculating the present value of estimated future cash flows related to the liability. Estimating the future ARO requires management to make estimates and judgments regarding the timing and existence of a liability, as well as what constitutes adequate restoration when considering current regulatory requirements. Inherent in the fair value calculation are numerous assumptions and judgments, including the ultimate costs, inflation factors, credit-adjusted discount rates, timing of settlement and changes in the legal, regulatory, environmental and political environments.

Derivative Instruments

Derivative Instruments	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments The Company utilizes derivative financial instruments to manage risks related to changes in crude oil and natural gas prices. The Company’s crude oil contracts settle monthly based on the average NYMEX WTI, and its natural gas contracts settle monthly based on the average NYMEX Henry Hub natural gas index price (“NYMEX HH”). The Company primarily utilizes fixed price swaps and collars to reduce the volatility of crude oil and natural gas prices on future expected production. Swaps are designed to establish a fixed price for the volumes under contract, while collars are designed to establish a minimum price (floor) and a maximum price (ceiling) for the volumes under contract. The Company may, from time to time, restructure existing derivative contracts or enter into new transactions to effectively modify the terms of current contracts in order to improve the pricing parameters in existing contracts. All derivative instruments are recorded on the Company’s Condensed Consolidated Balance Sheets as either assets or liabilities measured at fair value (see Note 6 – Fair Value Measurements). The Company has not designated any derivative instruments as hedges for accounting purposes and does not enter into such instruments for speculative trading purposes. If a derivative does not qualify as a hedge or is not designated as a hedge, the changes in fair value are recognized in the other income (expense) section of the Company’s Condensed Consolidated Statements of Operations as a net gain or loss on derivative instruments. Derivative settlements are reflected as investing activities on the Company’s Condensed Consolidated Statements of Cash Flows and represent net cash payments to or receipts from counterparties upon the maturity or liquidation of a derivative contract. On March 22, 2021, the Company entered into the Second Amendment to the Oasis Credit Facility (as defined in Note 11 –Long-Term Debt) to, among other things, reduce the rolling hedging requirement and add incremental flexibility to allow for restructuring of existing hedge positions (see Note 11 – Long-Term Debt). On May 17, 2021, the Company entered into a series of transactions with derivative counterparties to modify the swap price of certain commodity hedge contracts to $50.00 per barrel based on NYMEX WTI from weighted average prices of $40.72 per barrel, $43.57 per barrel and $43.68 per barrel for 2022, 2023 and 2024, respectively. The commodity contracts modified included total notional volumes of 6,346,000 barrels, 5,265,000 barrels and 434,000 barrels which settle in 2022, 2023 and 2024, respectively. The Company paid $82.4 million for the modification of these commodity derivative contracts, which is reflected as a cash outflow from investing activities in the Condensed Consolidated Statements of Cash Flows for the nine months ended September 30, 2021. At September 30, 2021 (Successor), the Company had the following outstanding commodity derivative instruments: Commodity Settlement Derivative Volumes Weighted Average Prices Fair Value Assets (Liabilities) Fixed Price Swaps Floor Ceiling (In thousands) Crude oil 2021 Fixed price swaps 2,639,000 Bbl $ 42.09 $ (83,180) Crude oil 2021 Two-way collar 728,000 Bbl $ 51.25 $ 68.24 (4,343) Crude oil 2022 Fixed price swaps 7,245,000 Bbl $ 49.02 (155,383) Crude oil 2022 Two-way collar 4,799,000 Bbl $ 49.50 $ 66.62 (38,493) Crude oil 2023 Fixed price swaps 5,265,000 Bbl $ 50.00 (73,146) Crude oil 2023 Two-way collar 4,380,000 Bbl $ 45.42 $ 65.05 (25,702) Crude oil 2024 Fixed price swaps 434,000 Bbl $ 50.00 (4,811) Crude oil 2024 Two-way collar 372,000 Bbl $ 45.00 $ 64.88 (1,586) Natural gas 2021 Fixed price swaps 3,680,000 MMBtu $ 2.84 (11,222) Natural gas 2022 Fixed price swaps 5,430,000 MMBtu $ 2.82 (10,987) $ (408,853) Permian Basin Sale Contingent Consideration. Pursuant to the Primary Permian Basin Sale PSA (defined in Note 10 – Divestitures), the Company is entitled to receive up to three earn-out payments of $25.0 million per year for each of 2023, 2024 and 2025 if the average daily settlement price of NYMEX WTI crude oil exceeds $60 per barrel for such year (the “Permian Basin Sale Contingent Consideration”). If the NYMEX WTI crude oil price for calendar year 2023 or 2024 is less than $45 per barrel, then each calendar year thereafter the buyer’s obligation to make any remaining earn-out payments is terminated. The Company determined that the Permian Basin Sale Contingent Consideration was an embedded derivative in accordance with the FASB Accounting Standards Codification 815, Derivatives and Hedging . The Company bifurcated the Permian Basin Sale Contingent Consideration from the host contract and accounted for it separately at fair value. The fair value of the Permian Basin Sale Contingent Consideration was estimated to be $32.9 million as of the close date on June 29, 2021. The Permian Basin Sale Contingent Consideration is marked-to-market each reporting period, with changes in fair value recognized as a net gain or loss on derivative instruments in other income (expense) on the Condensed Consolidated Statements of Operations. As of September 30, 2021, the estimated fair value of the Permian Basin Sale Contingent Consideration was $39.7 million, which was classified as a non-current derivative asset on the Condensed Consolidated Balance Sheet. See Note 6 – Fair Value Measurements and Note 10 – Divestitures for additional information. The following table summarizes the location and amounts of gains and losses from the Company’s derivative instruments recorded in the Company’s Condensed Consolidated Statements of Operations for the periods presented (in thousands): Successor Predecessor Successor Predecessor Three Months Ended September 30, 2021 Three Months Ended September 30, 2020 Nine Months Ended September 30, 2021 Nine Months Ended September 30, 2020 Derivative Instrument Statements of Operations Location Commodity derivative instruments Net gain (loss) on derivative instruments $ (108,647) $ (5,071) $ (557,199) $ 243,064 Contingent consideration Net gain on derivative instruments 6,857 — 6,857 — Contingent consideration Gain on sale of properties — — 32,860 — In accordance with the FASB’s authoritative guidance on disclosures about offsetting assets and liabilities, the Company is required to disclose both gross and net information about instruments and transactions eligible for offset in the statement of financial position as well as instruments and transactions subject to an agreement similar to a master netting agreement. The Company’s derivative instruments are presented as assets and liabilities on a net basis by counterparty, as all counterparty contracts provide for net settlement. No margin or collateral balances are deposited with counterparties, and as such, gross amounts are offset to determine the net amounts presented in the Company’s Condensed Consolidated Balance Sheets. The following table summarizes the location and fair value of all outstanding derivative instruments recorded in the Company’s Condensed Consolidated Balance Sheets: Successor September 30, 2021 Derivative Instrument Balance Sheet Location Gross Amount Gross Amount Offset Net Amount (In thousands) Derivatives assets: Contingent consideration Derivative instruments — non-current assets $ 39,717 $ — $ 39,717 Derivatives liabilities: Commodity contracts Derivative instruments — current liabilities $ 271,077 $ (4,740) $ 266,337 Commodity contracts Derivative instruments — non-current liabilities 164,614 (22,098) 142,516 Total derivatives liabilities $ 435,691 $ (26,838) $ 408,853 Successor December 31, 2020 Derivative Instrument Balance Sheet Location Gross Amount Gross Amount Offset Net Amount (In thousands) Derivatives assets: Commodity contracts Derivative instruments — current assets $ 467 $ — $ 467 Derivatives liabilities: Commodity contracts Derivative instruments — current liabilities $ 59,262 $ (2,318) $ 56,944 Commodity contracts Derivative instruments — non-current liabilities 38,426 (812) 37,614 Total derivatives liabilities $ 97,688 $ (3,130) $ 94,558

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 The following table sets forth the Company’s property, plant and equipment: Successor September 30, 2021 December 31, 2020 (In thousands) Proved oil and gas properties $ 731,292 $ 770,117 Less: Accumulated depreciation, depletion and amortization (70,343) (12,403) Proved oil and gas properties, net 660,949 757,714 Unproved oil and gas properties 2,293 40,211 Other property and equipment 962,174 935,950 Less: Accumulated depreciation (42,572) (5,088) Other property and equipment, net 919,602 930,862 Total property, plant and equipment, net $ 1,582,844 $ 1,728,787

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Acquisitions	Acquisitions Williston Basin Acquisition. On May 3, 2021, the Company entered into a purchase and sale agreement with QEP Energy Company (“QEP”), a wholly-owned subsidiary of Diamondback Energy, Inc., to acquire approximately 95,000 net acres in the Williston Basin, effective April 1, 2021, for an aggregate purchase price of $745.0 million, subject to customary purchase price adjustments (the “Williston Basin Acquisition”). The adjusted purchase price was $585.8 million, comprised of a deposit of $74.5 million paid on May 3, 2021 and $511.3 million paid at closing on October 21, 2021. The adjusted purchase price included customary purchase price adjustments, primarily related to the net cash flows from the effective date to the closing date. The Company funded the Williston Basin Acquisition with cash on hand, including proceeds from the Permian Basin Sale (defined in Note 10 – Divestitures ) and the Oasis Senior Notes (defined in Note 11 – Long-Term Debt ) . The Company is currently evaluating whether the Williston Basin Acquisition qualifies as a business combination or asset acquisition. The Company has engaged a third party valuation specialist and expects to complete the accounting in the fourth quarter of 2021.

Divestitures

Divestitures	9 Months Ended
	Sep. 30, 2021
Discontinued Operations and Disposal Groups [Abstract]
Divestitures	Divestitures Permian Basin Sale . On May 20, 2021, Oasis Petroleum Permian LLC (“OPP”), a wholly-owned subsidiary of the Company, entered into a purchase and sale agreement (the “Primary Permian Basin Sale PSA”) with Percussion Petroleum Operating II, LLC (“Percussion”). Pursuant to the Primary Permian Basin Sale PSA, OPP agreed to sell to Percussion its remaining upstream assets in the Texas region of the Permian Basin with an effective date of March 1, 2021 for an aggregate purchase price of $450.0 million (the “Primary Permian Basin Sale”). The aggregate purchase price consists of $375.0 million cash at closing and up to three earn-out payments of $25.0 million per year for each of 2023, 2024 and 2025 if the average daily settlement price of NYMEX WTI crude oil exceeds $60.00 per barrel for such year. On June 29, 2021, the Company completed the Primary Permian Basin Sale and received cash proceeds (after purchase price adjustments) of $347.3 million. In addition to the Primary Permian Basin Sale, the Company divested certain wellbore interests in the Texas region of the Permian Basin to separate buyers in the second quarter of 2021 and received cash proceeds (after purchase price adjustments) of $24.0 million (the “Additional Permian Basin Sale” and together with the Primary Permian Basin Sale, the “Permian Basin Sale”). The assets divested in the Permian Basin Sale were in the Company’s E&P segment. During the three and nine months ended September 30, 2021, the Company recorded income before income taxes related to the Permian Basin Sale assets of $5.9 million and $268.1 million, respectively, which included a gain on sale of properties of $4.9 million and $227.4 million, respectively. During the three and nine months ended September 30, 2020 (Predecessor), the Company recorded income before income taxes related to the assets divested in the Permian Basin Sale of $12.1 million and loss before income taxes of $883.0 million, respectively. The Company accounted for revenues and expenses related to assets divested in the Permian Basin Sale as income from continuing operations in the Condensed Consolidated Statements of Operations because the Permian Basin Sale did not cause a strategic shift for the Company and as a result, did not qualify as discontinued operations under FASB Accounting Standards Codification 205-20, Presentation of financial statements – Discontinued Operations .

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt The Company’s long-term debt consists of the following: Successor September 30, 2021 December 31, 2020 (In thousands) Oasis Credit Facility $ — $ 260,000 Oasis Senior Notes 400,000 — Less: unamortized deferred financing costs on Oasis Senior Notes (8,495) — Total Oasis Guarantors 391,505 260,000 OMP Credit Facility 210,000 450,000 OMP Senior Notes 450,000 — Less: unamortized deferred financing costs on OMP Senior Notes (9,610) — Total unrestricted subsidiaries 650,390 450,000 Total long-term debt, net $ 1,041,895 $ 710,000 Oasis Debt Oasis Credit Facility The Company has a senior secured revolving credit facility (the “Oasis Credit Facility”) among Oasis Petroleum Inc., as parent, OPNA, as borrower, and Wells Fargo Bank, N.A. (“Wells Fargo”), as administrative agent and the lenders party thereto, which has a maturity date of May 19, 2024. On March 22, 2021, the Company entered into the Second Amendment to the Oasis Credit Facility to, among other things, (i) provide for the occurrence of the transactions pursuant to the Midstream Simplification, (ii) decrease the borrowing base from $575.0 million to $500.0 million, (iii) decrease the aggregate lender commitments from $575.0 million to $450.0 million, (iv) provide the ability to initiate certain share-repurchases, (v) reduce the rolling hedging requirement and add incremental flexibility to allow for restructuring of existing hedge positions and (vi) decrease the LIBOR floor from 1.00% to 0.25%. On May 3, 2021, the Company entered into the Third Amendment to the Oasis Credit Facility to, among other things, (i) provide the ability to incur loans pursuant to a customary bridge loan facility, (ii) add customary terms allowing for the incurrence of second liens, (iii) eliminate restrictions on the ability to make deposits of cash and/or cash equivalents in connection with any letter of intent or purchase agreement for certain acquisitions or investments, (iv) remove limitations on the making of capital expenditures and (v) provide for improvements and conforming changes to terms to facilitate acquisitions and investments. On May 21, 2021, the Company entered into the Fourth Amendment to the Oasis Credit Facility (the “Fourth Amendment”) to, among other things, (i) provide that no borrowing base reduction shall occur in connection with any issuance of senior notes in an aggregate principal amount not in excess of $550.0 million issued after the effective date of the Fourth Amendment and prior to the effectiveness of the scheduled redetermination to occur on or about October 1, 2021, (ii) reduce the borrowing base by $100.0 million upon consummation of the Primary Permian Basin Sale and (iii) increase the borrowing base by $250.0 million upon consummation of the Williston Basin Acquisition. The borrowing base increased to $900.0 million after the Company completed the semi-annual redetermination of the borrowing base on October 21, 2021 in connection with the Fifth Amendment (defined below). The Fourth Amendment also amends the exceptions from the restricted payments negative covenant to provide increased restricted payment flexibility, permitting unlimited restricted payments subject to (x) no event of default under the Oasis Credit Facility, (y) at least 25% availability under the Oasis Credit Facility and (z) the pro forma leverage ratio being not more than 1.5 to 1.0; provided that if the conditions described in clauses (x) and (y) are satisfied and the pro forma leverage ratio is less than 2.0 to 1.0, but more than 1.5 to 1.0, restricted payments are permitted in an amount such that all restricted payments made in reliance on such exception since the closing date of the Oasis Credit Facility will not exceed the positive amount of free cash flow. On October 21, 2021, the Company entered into the Fifth Amendment to the Oasis Credit Facility (the “Fifth Amendment”). In connection with the Fifth Amendment, the semi-annual redetermination of the Company’s borrowing base was completed which, effective October 21, 2021, increased the borrowing base to $900.0 million and reaffirmed the aggregated lender commitments of $450.0 million. At September 30, 2021, the Company had no borrowings outstanding and $1.3 million of outstanding letters of credit under the Oasis Credit Facility, resulting in an unused borrowing capacity of $398.7 million. During the three months ended September 30, 2021, there were no borrowings outstanding under the Oasis Credit Facility. For the nine months ended September 30, 2021, the weighted average interest rate incurred on borrowings under the Oasis Credit Facility was 4.2%. The fair value of the Oasis Credit Facility approximates its carrying value since borrowings under the Oasis Credit Facility bear interest at variable rates, which are tied to current market rates. The Oasis Credit Facility contains customary events of default, as well as cross-default provisions with other indebtedness of OPNA and the restricted subsidiaries under the Oasis Credit Facility. If an event of default occurs and is continuing, the lenders may declare all amounts outstanding under the Oasis Credit Facility to be immediately due and payable. There are no cross-default provisions between the Oasis Credit Facility and the indebtedness of OMP and its restricted subsidiaries that are applicable subsequent to the Midstream Simplification. The Company was in compliance with the financial covenants under the Oasis Credit Facility at September 30, 2021. Oasis Bridge Facility On May 3, 2021, the Company entered into a commitment letter with J.P. Morgan Chase Bank, N.A., Wells Fargo and Wells Fargo Securities, LLC (the “Arrangers”) pursuant to which the Arrangers committed to provide the Company a $500.0 million senior secured second lien facility (the “Oasis Bridge Facility”) to partially finance the transactions contemplated by the Williston Basin Acquisition. Prior to being drawn, the Oasis Bridge Facility was replaced with the Oasis Senior Notes (defined below), which terminated all obligations under the Oasis Bridge Facility. During the nine months ended September 30, 2021, the Company incurred aggregate fees in connection with the Oasis Bridge Facility of $7.8 million, which were recorded to interest expense on the Company’s Condensed Consolidated Statement of Operations. No fees were incurred during the three months ended September 30, 2021. Oasis Senior Notes On June 9, 2021, the Company issued in a private placement $400.0 million of 6.375% senior unsecured notes due June 1, 2026 (the “Oasis Senior Notes”). The Oasis Senior Notes were issued at par and resulted in net proceeds of $393.0 million, after deducting the underwriters’ discounts and commissions. The proceeds were held in a standalone bank account at September 30, 2021 and were used to fund a portion of the consideration for the Williston Basin Acquisition upon its completion on October 21, 2021 (see Note 9 – Acquisitions ) . In connection with the issuance of the Oasis Senior Notes, the Company recorded deferred financing costs of $9.0 million, which are being amortized over the term of the notes. The fair value of the Oasis Senior Notes, which are publicly traded among qualified institutional investors and represent a Level 1 fair value measurement, was $419.0 million at September 30, 2021. Interest on the Oasis Senior Notes is payable semi-annually on June 1 and December 1 of each year, commencing on December 1, 2021. The Oasis Senior Notes are guaranteed on a senior unsecured basis by the Company, along with its wholly-owned subsidiaries (the “Oasis Guarantors”). These guarantees are full and unconditional and joint and several among the Oasis Guarantors, subject to certain customary release provisions. The indentures governing the Oasis Senior Notes contain customary events of default. In addition, the indenture governing the Oasis Senior Notes contains cross-default provisions with other indebtedness of Oasis and its restricted subsidiaries; however, there are no cross-default provisions with the indebtedness of OMP and its restricted subsidiaries. The indentures governing the Oasis Senior Notes restrict the Company’s ability and the ability of certain of its subsidiaries to, among other things: (i) make investments; (ii) incur additional indebtedness or issue preferred stock; (iii) create liens; (iv) sell assets; (v) enter into agreements that restrict dividends or other payments by restricted subsidiaries; (vi) consolidate, merge or transfer all or substantially all of the Company’s assets with another company; (vii) enter into transactions with affiliates; (viii) pay dividends or make other distributions on capital stock or prepay subordinated indebtedness; and (ix) create unrestricted subsidiaries. These covenants are subject to a number of important exceptions and qualifications. If at any time when the Oasis Senior Notes are rated investment grade by two out of the three rating agencies and no default (as defined in the indentures) has occurred and is continuing, many of such covenants will terminate and the Company will cease to be subject to such covenants. The Company was in compliance with the terms of the indentures for the Oasis Senior Notes as of September 30, 2021. OMP Debt OMP Credit Facility OMP has a senior secured revolving credit facility (the “OMP Credit Facility”) among OMP, as parent, OMP Operating LLC, as borrower, Wells Fargo, as administrative agent and the lenders party thereto. On March 22, 2021, OMP entered into the Fourth Amendment to the OMP Credit Facility (the “OMP Credit Facility Fourth Amendment”) to, among other things, (i) provide for the occurrence of the transactions pursuant to the Midstream Simplification, (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 OMP Senior Notes (defined below), (vi) decrease the aggregate lender commitments from $575.0 million to $450.0 million, (vii) increase pricing for credit under the OMP Credit Facility and (viii) extend the maturity date from September 25, 2022 until at least September 30, 2024. Following the OMP Credit Facility Fourth Amendment, the applicable margin for borrowings under the OMP Credit Facility varies from (a) in the case of LIBOR loans (defined in the OMP Credit Facility as Eurodollar Loans), 2.25% to 3.25%, and (b) in the case of domestic bank prime rate interest loans (defined in the OMP Credit Facility as ABR Loans) or swingline loans, 1.25% to 2.25%. The unused portion of the OMP 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 OMP 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 OMP Credit Facility was 2.5% and 2.4%, respectively. The fair value of the OMP Credit Facility approximates its carrying value since borrowings under the OMP Credit Facility bear interest at variable rates, which are tied to current market rates. The OMP Credit Facility contains customary events of default, as well as cross-default provisions with other indebtedness of OMP and the restricted subsidiaries under the OMP Credit Facility. If an event of default occurs and is continuing, the lenders may declare all amounts outstanding under the OMP Credit Facility to be immediately due and payable. There are no cross-default provisions between the OMP Credit Facility and the indebtedness of Oasis and its restricted subsidiaries. OMP was in compliance with the financial covenants under the OMP Credit Facility at September 30, 2021. OMP Senior Notes On March 30, 2021, OMP and OMP Finance Corp. (“OMP Finance” and together with OMP, the “OMP Issuers”) issued in a private placement $450.0 million of 8.00% senior unsecured notes due April 1, 2029 (the “OMP Senior Notes”). The OMP Senior Notes were issued at par and resulted in net proceeds, after deducting the underwriters’ gross spread, of $442.1 million. OMP used the net proceeds from the OMP Senior Notes to: (i) make a distribution to OMS Holdings of $231.5 million in connection with the Midstream Simplification, (ii) repay $204.0 million of outstanding principal borrowings and $0.5 million of accrued interest under the OMP Credit Facility and (iii) pay approximately $6.1 million in fees and other expenses. In connection with the issuance of the OMP Senior Notes, OMP recorded deferred financing costs of $10.2 million, which are being amortized over the term of the notes. The fair value of the OMP Senior Notes, which are publicly traded among qualified institutional investors and represent a Level 1 fair value measurement, was $468.0 million at September 30, 2021. Interest on the OMP Senior Notes is payable semi-annually on April 1 and October 1 of each year, commencing on October 1, 2021. The OMP Senior Notes are fully and unconditionally guaranteed on a senior unsecured basis by the OMP Issuers, along with OMP’s wholly-owned subsidiaries (the “OMP Guarantors”). The OMP Senior Notes guarantees are joint and several obligations of the OMP Guarantors. The OMP Issuers and the OMP 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 OMP Senior Notes contains certain covenants that, subject to certain exceptions and qualifications, among other things, limit OMP’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 pay dividends or make distributions on equity interests or redeem, repurchase or retire equity interests or subordinated indebtedness, (iv) transfer or sell assets including equity of restricted subsidiaries, (v) agree to payment restrictions affecting OMP’s restricted subsidiaries, (vi) consolidate, merge, sell or otherwise dispose of all or substantially all of its assets, (vii) enter into transactions with affiliates, (viii) incur liens and (ix) designate certain of OMP’s subsidiaries as unrestricted subsidiaries. The indenture governing the OMP Senior Notes contains cross-default provisions with other indebtedness of OMP and its restricted subsidiaries; however, there are no cross-default provisions with the indebtedness of Oasis and its restricted subsidiaries.

Asset Retirement Obligations

Asset Retirement Obligations	9 Months Ended
	Sep. 30, 2021
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement Obligations	Asset Retirement Obligations The following table reflects the changes in the Company’s ARO during the nine months ended September 30, 2021: (In thousands) Balance at December 31, 2020 (Successor) $ 48,594 Liabilities incurred during period 409 Liabilities settled during period (322) Accretion expense during period 3,016 Revisions to estimates 194 Liabilities settled through divestitures (4,844) Balance at September 30, 2021 (Successor) $ 47,047 Accretion expense is included in depreciation, depletion and amortization on the Company’s Condensed Consolidated Statements of Operations. At September 30, 2021 and December 31, 2020, the current portion of the total ARO balance was $1.1 million and $2.2 million, respectively, and is included in accrued liabilities on the Company’s Condensed Consolidated Balance Sheets.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s effective tax rate for both the three and nine months ended September 30, 2021 (Successor) was 0.0%. The Company’s effective tax rates for the three and nine months ended September 30, 2020 (Predecessor) were 9.8% and 5.5%, respectively. The effective tax rates for the three and nine months ended September 30, 2021 and 2020 were lower than the statutory federal rate of 21% primarily as a result of the Company’s valuation allowance, which was initially recorded against substantially all of the Company’s net deferred tax assets as of March 31, 2020 and was maintained as of September 30, 2021. The Company’s estimated valuation allowance as of September 30, 2021 was $529.8 million, which decreased $35.6 million from $565.4 million as of December 31, 2020. The Company concluded it is more likely than not that some or all of the benefits from its deferred tax assets will not be realized, and as such, recorded a valuation allowance on these assets. Management assesses the available positive and negative evidence, including future reversals of temporary differences, tax-planning strategies and future taxable income, to estimate whether sufficient future taxable income will be generated to permit the use of deferred tax assets. If the Company concludes it is more likely than not that a portion, or all, of its deferred tax assets will not be realized, the deferred tax asset is reduced by a valuation allowance. A significant piece of objective negative evidence evaluated is the cumulative loss incurred over recent years, excluding the impact of the voluntary restructuring under Chapter 11 of the Bankruptcy Code in 2020. Such objective negative evidence limits the ability to consider other subjective positive evidence. The amount of the deferred tax asset considered realizable could be adjusted if estimates of future taxable income change or if objective negative evidence, in the form of cumulative losses, is no longer present and additional weight is given to subjective evidence such as future growth. The Company evaluates the appropriateness of its valuation allowance on a quarterly basis.

Equity-Based Compensation

Equity-Based Compensation	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Equity-Based Compensation	Equity-Based Compensation Successor Equity-Based Compensation The Compensation Committee of the Board of Directors approved the grant of certain awards under the Company’s 2020 Long Term Incentive Plan (“2020 LTIP”), which consists of restricted stock units (“RSUs”), performance share units (“PSUs”) and leveraged stock units (“LSUs”). The Company accounts for RSUs, PSUs and LSUs as equity classified awards in accordance with the FASB’s authoritative guidance for share-based payments. Restricted stock units. RSUs are contingent shares that are scheduled to vest 25% each year over a four-year period to promote retention of key employees. The fair value is based on the closing price of the Company’s common stock on the date of grant or, if applicable, the date of modification. Compensation expense is recognized ratably over the requisite service period. During the nine months ended September 30, 2021, the Company granted 443,836 RSUs with a weighted average grant date per share value of $51.64. During the three and nine months ended September 30, 2021, the Company recorded equity-based compensation expense related to RSUs of $1.4 million and $3.5 million, respectively, in general and administrative expenses on its Condensed Consolidated Statements of Operations. Performance share units. PSUs are contingent shares that may be earned over three-year and four-year performance periods. The number of PSUs to be earned is subject to a market condition, which is based on a comparison of the total shareholder return (“TSR”) achieved with respect to shares of the Company’s common stock against the TSR achieved by a defined peer group at the end of the applicable performance periods, with 50% of the PSU awards eligible to be earned based on performance relative to a certain group of the Company’s oil and gas peers and 50% of the PSU awards eligible to be earned based on performance relative to the broad-based Russell 2000 index. Depending on the Company’s TSR performance relative to the defined peer group, award recipients may earn between 0% and 150% of target. During the nine months ended September 30, 2021, the Company granted 183,915 PSUs with a weighted average grant date per share value of $63.95. During the three and nine months ended September 30, 2021, the Company recorded equity-based compensation expense related to PSUs of $0.9 million and $2.2 million, respectively, in general and administrative expenses on its Condensed Consolidated Statements of Operations. Leveraged stock units. LSUs are contingent shares that may be earned over a three-year or four-year performance period. The number of LSUs to be earned is subject to a market condition, which is based on the TSR performance of the Company’s common stock measured against specific premium return objectives. Depending on the Company’s TSR performance, award recipients may earn between 0% and 300% of target; however, the number of shares delivered in respect to these awards during the grant cycle may not exceed ten times the fair value of the award on the grant date. During the nine months ended September 30, 2021, the Company granted 262,406 LSUs with a weighted average grant date per share value of $78.79. During the three and nine months ended September 30, 2021, the Company recorded equity-based compensation expense related to LSUs of $1.6 million and $4.0 million, respectively, in general and administrative expenses on its Condensed Consolidated Statements of Operations. Fair value assumptions. The aggregate grant date fair value of PSUs and LSUs was determined by a third-party valuation specialist using a Monte Carlo simulation model. The key valuation inputs were: (i) the forecast period, (ii) risk-free interest rate, (iii) implied equity volatility, (iv) stock price on the date of grant and, for PSUs, (v) correlation coefficient. The risk-free interest rates are the U.S. Treasury bond rates on the date of grant that correspond to each performance period. Implied equity volatility is derived by solving for an asset volatility and equity volatility based on the leverage of the Company and each of its peers. For the PSUs, the correlation coefficient measures the strength of the linear relationship between and amongst the Company and its peers based on historical stock price data. The following table summarizes the assumptions used in the Monte Carlo simulation model to determine the grant date fair value and associated equity-based compensation expenses by grant date: Grant date January 18, 2021 February 11, 2021 April 13, 2021 Forecast period (years) 3 - 4 3 - 4 3 - 4 Risk-free interest rates 0.2% - 0.3% 0.2% - 0.3% 0.3% - 0.6% Implied equity volatility 55% - 60% 55% - 60% 45% - 50% Stock price on date of grant $44.41 $49.66 $68.07 Restricted stock awards. The Company has granted restricted stock awards to its directors under the 2020 LTIP, which vest one-third annually over a three-year period subject to a service condition. The fair value of restricted stock awards is based on the closing price of the Company’s common stock on the date of grant or, if applicable, the date of modification. Compensation expense is recognized ratably over the requisite service period. During the three and nine months ended September 30, 2021, the Company recorded equity-based compensation expense for restricted stock awards of $0.3 million and $0.9 million, respectively, in general and administrative expenses on its Condensed Consolidated Statements of Operations. Class B Units in OMP GP OMP GP previously granted restricted Class B Units to certain employees, including OMP’s named executive officers, as consideration for services to the Company. On March 30, 2021, in connection with the Midstream Simplification, certain Class B Units representing membership interests in OMP GP that were previously issued to certain of OMP’s named executive officers were converted into and exchanged for the right to receive restricted common units in OMP, subject to the following vesting schedule: (i) 34% vested on March 30, 2021, (ii) 33% will vest on March 30, 2022 and (iii) 33% will vest on March 30, 2023. As of September 30, 2021, the unamortized grant date fair value related to the unvested OMP restricted common units was $0.4 million and will be recognized over a remaining life of approximately two years. Predecessor Equity-Based Compensation The Predecessor previously granted equity-classified restricted stock awards and PSUs under its Amended and Restated 2010 Long Term Incentive Plan (the “Predecessor 2010 LTIP”). For the three and nine months ended September 30, 2020, the Predecessor recorded equity-based compensation expense of $3.1 million and $10.6 million, respectively, related to restricted stock awards and $1.6 million and $5.7 million, respectively, related to PSUs in general and administrative expenses on its Condensed Consolidated Statements of Operations. On the Emergence Date and pursuant to the Company’s restructuring plan, all outstanding unvested restricted stock awards and PSUs granted under the Predecessor 2010 LTIP vested, and there were no outstanding Predecessor restricted stock awards and PSUs at September 30, 2021 or December 31, 2020. 2020 Incentive Compensation Program . In the second quarter of 2020, the board of directors of the Predecessor implemented a revised 2020 incentive compensation program pursuant to which all 2020 equity-based awards previously granted were forfeited and concurrently replaced with cash retention incentives. In connection with the 2020 cash incentive compensation program, the Predecessor recorded $5.9 million and $12.4 million in general and administrative expenses on its Condensed Consolidated Statements of Operations for the three and nine months ended September 30, 2020, respectively.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity Dividends . On February 24, 2021, the Company declared a dividend of $0.375 per share of common stock. The dividend of $7.5 million was paid on March 22, 2021 to shareholders of record as of March 8, 2021. On May 3, 2021, the Company declared a dividend of $0.375 per share of common stock. The dividend of $7.5 million was paid on May 31, 2021 to shareholders of record as of May 17, 2021. On June 29, 2021, the Company declared a special dividend of $4.00 per share of common stock (the “Special Dividend”). The Special Dividend of $80.0 million was paid on July 21, 2021 to shareholders of record as of July 9, 2021. On August 3, 2021, the Company declared a dividend of $0.375 per share of common stock. The dividend of $7.5 million was paid on August 27, 2021 to shareholders of record as of August 16, 2021. On October 26, 2021, the Company declared a dividend of $0.50 per share of common stock payable on November 29, 2021 to shareholders of record as of November 15, 2021. Future dividend payments will depend on the Company’s earnings, financial condition, capital requirements, level of indebtedness, statutory and contractual restrictions applicable to the payment of dividends and other considerations that the Board of Directors deems relevant. Share repurchase program . In March 2021, the Board of Directors authorized a share-repurchase program covering up to $100.0 million of the Company’s common stock which expires on December 31, 2022. During the nine months ended September 30, 2021, the Company repurchased an aggregate amount of 190,783 shares of common stock at a weighted average price of $76.30 per common share for a total cost of $14.6 million. There were no share repurchases made subsequent to September 30, 2021, except from October 28, 2021 through November 2, 2021, the Company repurchased 156,519 shares of common stock at a weighted average price of $121.22 per common share for a total cost of $19.0 million. Warrants . As of September 30, 2021, there were 1,615,555 warrants outstanding. During the three and nine months ended September 30, 2021, there were 2,791 and 6,050 warrants exercised, respectively. The warrants, which are classified as equity, are exercisable to purchase one share of common stock per warrant at an initial exercise price of $94.57 per warrant. In connection with the Special Dividend, the exercise price decreased from $94.57 per warrant to $90.57 per warrant on July 12, 2021. The warrants are exercisable from the date of issuance until November 19, 2024, at which time all unexercised warrants will expire and the rights of the holders of such warrants to purchase common stock will terminate. The number of shares of common stock for which a warrant is exercisable and the exercise price, are subject to adjustment from time to time upon the occurrence of certain events, including: (1) stock splits, reverse stock splits or stock dividends to holders of common stock or (2) a reclassification in respect of common stock. OMP Equity Offering. On June 29, 2021, OMP 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 “OMP Equity Offering”) and received net proceeds of $86.7 million, after deducting underwriting discounts, commissions and offering expenses. OMP used the proceeds from the OMP Equity Offering to redeem 3,623,188 common units held by Oasis for $87.0 million (the “OMP Unit Redemption”). Following the OMP Unit Redemption, the Company owns approximately 70%, and non-controlling interests own approximately 30% of OMP’s outstanding common units. Tax benefits preservation plan. On August 3, 2021, the Board of Directors adopted a Tax Benefits Preservation Plan (the “Tax Plan”) designed to protect the availability of the Company’s Tax Benefits, which may be utilized in certain circumstances to reduce the Company’s future income tax obligations. In adopting the Tax Plan, the Board of Directors declared a dividend of one preferred share purchase right (a “Right”) for each outstanding share of the Company’s common stock. The Rights will trade with the Company’s common stock and will expire at the close of business on the earlier of August 3, 2024 (three years from adoption) and the date upon which the Board of Directors determines that no Tax Benefits remain available or earlier, as described in more detail in the Tax Plan. The Rights will be exercisable if, among other things, a person or group of persons acquires 4.95% or more of the Company’s outstanding common stock.

Earnings (Loss) Per Share

Earnings (Loss) Per Share	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	Earnings (Loss) Per Share Basic earnings (loss) per share is computed by dividing the earnings (loss) attributable to Oasis common stockholders by the weighted average number of shares outstanding for the periods presented. The calculation of diluted earnings (loss) per share includes the effect of potentially dilutive shares outstanding for the period using the treasury stock method, unless its effect is anti-dilutive. For the Successor period, potentially dilutive shares outstanding include unvested restricted stock awards, warrants and contingently issuable shares related to RSUs, PSUs and LSUs. For the Predecessor period, potentially dilutive shares outstanding included Predecessor unvested restricted stock awards, Predecessor contingently issuable shares related to PSUs and Predecessor senior convertible notes. There were no adjustments made to the income (loss) attributable to Oasis available to common stockholders in the calculation of diluted earnings (loss) per share during either the Successor period or Predecessor period. The following table summarizes the basic and diluted weighted average common shares outstanding and the weighted average common shares excluded from the calculation of diluted weighted average common shares outstanding due to the anti-dilutive effect for the periods presented (in thousands): Successor Predecessor Successor Predecessor Three Months Ended September 30, 2021 Three Months Ended September 30, 2020 Nine Months Ended September 30, 2021 Nine Months Ended September 30, 2020 Weighted average common shares outstanding: Basic 19,812 318,287 19,905 317,365 Dilutive effect of equity-classified awards 956 — 603 — Dilutive effect of warrants 18 — — — Diluted 20,786 318,287 20,508 317,365 Anti-dilutive weighted average common shares: Potential common shares 2,152 4,292 2,295 7,420 For the three and nine months ended September 30, 2021 (Successor), the diluted earnings per share calculation excludes the impact of unvested share based awards and outstanding warrants that were anti-dilutive under the treasury stock method. In addition, for the three and nine months ended September 30, 2020 (Predecessor), the Company incurred a net loss, and therefore the diluted loss per share calculation for those periods excludes the anti-dilutive effect of all potentially dilutive shares.

Business Segment Information

Business Segment Information	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Business Segment Information	Business Segment Information The Company has two reportable segments: E&P and midstream. The Company’s E&P business segment is engaged in the acquisition and development of oil and gas properties. Revenues for the E&P business segment are primarily derived from the sale of crude oil and natural gas production. The Company’s midstream business segment performs midstream services including: (i) natural gas gathering, compression, processing and gas lift supply; (ii) crude oil gathering, terminaling and transportation; (iii) produced and flowback water gathering and disposal; and (iv) freshwater supply and distribution. Revenues for the midstream segment are derived from performing these services for the Company’s E&P segment as well as third-party producers. The revenues and expenses related to services provided by the midstream segment for the Company’s ownership interests are eliminated in consolidation, and only the revenues and expenses related to non-affiliated interest owners and third-party customers are included in the Company’s Condensed Consolidated Statements of Operations. The Company’s corporate activities have been allocated to the supported business segments accordingly. Management evaluates the performance of the Company’s business segments based on operating income (loss), which is defined as segment operating revenues less operating expenses, including depreciation, depletion and amortization. The following table summarizes financial information for the Company’s two business segments for the periods presented: E&P Midstream Eliminations Consolidated (In thousands) Successor Three months ended September 30, 2021: Revenues from non-affiliates $ 335,327 $ 66,712 $ — $ 402,039 Inter-segment revenues — 41,561 (41,561) — Total revenues 335,327 108,273 (41,561) 402,039 Operating income 153,125 51,289 (824) 203,590 Total other expense, net (109,085) (11,173) — (120,258) Income before income taxes $ 44,040 $ 40,116 $ (824) $ 83,332 Lease operating expenses $ 44,914 $ — $ (15,607) $ 29,307 Gathering, processing and transportation expenses 30,028 — (13,628) 16,400 General and administrative expenses (1) 15,702 6,668 (2,856) 19,514 Equity-based compensation expenses 4,144 143 — 4,287 Predecessor Three months ended September 30, 2020: Revenues from non-affiliates $ 215,636 $ 55,423 $ — $ 271,059 Inter-segment revenues — 54,638 (54,638) — Total revenues 215,636 110,061 (54,638) 271,059 Operating income (loss) (8,603) 48,132 (1,005) 38,524 Total other expense, net (87,953) (2,812) — (90,765) Income (loss) before income taxes $ (96,556) $ 45,320 $ (1,005) $ (52,241) Lease operating expenses $ 41,235 $ — $ (11,882) $ 29,353 Gathering, processing and transportation expenses 32,003 — (11,675) 20,328 General and administrative expenses (1) 44,088 9,089 (3,926) 49,251 Equity-based compensation expenses 4,502 400 (68) 4,834 Successor Nine months ended September 30, 2021: Revenues from non-affiliates $ 947,013 $ 203,545 $ — $ 1,150,558 Inter-segment revenues — 125,007 (125,007) — Total revenues 947,013 328,552 (125,007) 1,150,558 Operating income (loss) 593,493 139,946 (3,441) 729,998 Total other income (expense), net (574,583) (26,039) — (600,622) Income before income taxes $ 18,910 $ 113,907 $ (3,441) $ 129,376 Lease operating expenses $ 146,414 $ — $ (47,526) $ 98,888 Gathering, processing and transportation expenses 90,920 — (38,324) 52,596 General and administrative expenses (1) 47,084 23,403 (10,026) 60,461 Equity-based compensation expenses 10,518 669 — 11,187 Predecessor Nine months ended September 30, 2020: Revenues from non-affiliates $ 668,849 $ 156,360 $ — $ 825,209 Inter-segment revenues — 160,377 (160,377) — Total revenues 668,849 316,737 (160,377) 825,209 Operating income (loss) (4,866,759) 36,526 (4,995) (4,835,228) Total other income (expense), net 140,580 (38,568) — 102,012 Loss before income taxes $ (4,726,179) $ (2,042) $ (4,995) $ (4,733,216) Lease operating expenses $ 144,912 $ — $ (36,182) $ 108,730 Gathering, processing and transportation expenses 105,897 — (32,340) 73,557 General and administrative expenses (1) 103,051 26,995 (12,178) 117,868 Equity-based compensation expenses 15,909 1,031 (409) 16,531 Successor At September 30, 2021: Property, plant and equipment, net $ 692,271 $ 893,333 $ (2,760) $ 1,582,844 Total assets 1,939,695 1,062,577 (2,760) 2,999,512 At December 31, 2020: Property, plant and equipment, net $ 837,020 $ 892,043 $ (276) $ 1,728,787 Total assets 1,093,253 1,066,060 (276) 2,159,037 ___________________ (1) Includes equity-based compensation expenses.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies As of September 30, 2021, the Company’s material off-balance sheet arrangements and transactions include $6.7 million in outstanding letters of credit under its revolving credit facilities and $10.2 million in net surety bond exposure issued as financial assurance on certain agreements. As of September 30, 2021, there have been no material changes to the Company’s commitments and contingencies disclosed in Note 24 — Commitments and Contingencies in the Company’s 2020 Annual Report other than the items discussed below. Volume commitment agreements. As of December 31, 2020, the Company had $32.6 million of estimable future commitments pursuant to volume commitment agreements related to properties divested in the Primary Permian Basin Sale. Such volume commitment agreements were assigned to Percussion at closing, and the Company no longer has any remaining volume commitments associated with these agreements. In addition, the Company previously disclosed in its 2020 Annual Report potential future obligations associated with a continuous development agreement (the “CDA”) concerning certain drilling and development obligations in the Permian Basin. The CDA was assigned to Percussion upon closing of the Primary Permian Basin Sale, and the Company does not have any future obligations associated with this agreement. In August 2021, certain escalations became effective pursuant to an agreement to transport a minimum quantity of crude oil volumes in the Williston Basin. As of September 30, 2021, the Company’s estimable future commitment under this agreement was $258.6 million and has a remaining term of approximately 7 years. Litigation. The Company is party to various legal and/or regulatory proceedings from time to time arising in the ordinary course of business. When the Company determines that a loss is probable of occurring and is reasonably estimable, the Company accrues an undiscounted liability for such contingencies based on its best estimate using information available at the time. The Company discloses contingencies where an adverse outcome may be material, or in the judgment of management, the matter should otherwise be disclosed. Mandan, Hidatsa and Arikara Nation (“MHA Nation”) Title Dispute. This matter relates to certain leases acquired by the Company from QEP in October 2021: in June 2018, the MHA Nation notified QEP of its position that QEP has no valid lease covering certain minerals underlying the Missouri and Little Missouri Riverbeds on the Fort Berthold Reservation in North Dakota. The MHA Nation also passed a resolution purporting to rescind those portions of QEP's IMDA lease covering the disputed minerals underlying the Missouri River. QEP responded in September 2018 stating that the minerals underlying the Missouri River are properly leased. In May 2020, the Office of the Solicitor of the United States Department of the Interior (the “Department of the Interior”) issued an opinion (the “Missouri River Opinion”) finding that the State of North Dakota, not the MHA nation, is the legal owner of the minerals underlying the Missouri River. The MHA Nation filed actions in two federal courts seeking to overturn the May 2020 decision, and in March 2021, the Department of the Interior withdrew the Missouri River Opinion.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On October 26, 2021, the Company announced that on October 25, 2021, OMP and OMP GP 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 OMP (the “LP Merger”), with OMP surviving the LP Merger as a subsidiary of Crestwood, and GP Merger Sub will merge with and into OMP GP (the “GP Merger” and, together with the LP Merger, the “Mergers”), with OMP GP surviving the GP Merger as a wholly-owned subsidiary of Crestwood. Under the terms of the Merger Agreement, Oasis, as a unitholder of OMP, will receive $160.0 million in cash in addition to approximately 21.0 million common units of Crestwood in aggregate in exchange for its ownership of OMP common units and non-economic general partner stake in OMP GP. At the effective time of the Mergers (the “Effective Time”): (i) 6,520,944 common units representing limited partner interests in OMP (“OMP Common Units”) issued and outstanding immediately prior to the Effective Time and owned by OMS Holdings (such OMP 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 OMP Common Unit issued and outstanding immediately prior to the Effective Time owned by the Company or its subsidiaries (other than OMP) (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 OMP 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 OMP GP 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, the Company is expected to own approximately 22% of the Crestwood Common Units. The Mergers were unanimously approved by the Board of Directors of both Oasis and Crestwood and have also been unanimously approved by the Board of Directors and Conflicts Committee of OMP GP. The Mergers are expected to close in the first quarter of 2022 and are subject to customary closing conditions.

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 unaudited condensed consolidated financial statements of the Company have not been audited by the Company’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 the fair statement of the Company’s financial position, have been included. Management has made certain estimates and assumptions that affect reported amounts in the unaudited 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 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 Company’s audited consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 (“2020 Annual Report”).
Consolidation	Consolidation. The accompanying unaudited condensed consolidated financial statements of the Company include the accounts of Oasis, its wholly-owned subsidiaries and OMP. The Company has determined that the partners with equity at risk in OMP lack the authority, through voting rights or similar rights, to direct the activities that most significantly impact OMP’s economic performance. Therefore, as the limited partners of OMP do not have substantive kick-out or substantive participating rights over its general partner, OMP GP LLC (“OMP GP”), OMP is a variable interest entity. Through the Company’s ownership of OMP GP, the Company has the authority to direct the activities that most significantly affect economic performance and the right to receive benefits that could be potentially significant to OMP. Therefore, the Company is the primary beneficiary and consolidates OMP. The Company records a non-controlling interest for the ownership interest held by public unitholders in OMP. As of September 30, 2021, Oasis owns approximately 70% of OMP. All intercompany balances and transactions have been eliminated upon consolidation.
Fresh Start Accounting	Fresh start accounting. On November 19, 2020 (the “Emergence Date”), the Company emerged from bankruptcy and adopted fresh start accounting in accordance with the Financial Accounting Standards Board’s (“FASB”) Accounting Standards Codification 852, Reorganizations , which resulted in a new basis of accounting and the Company becoming a new entity for financial reporting purposes. As a result of the adoption of fresh start accounting, the condensed consolidated financial statements after the Emergence Date are not comparable to the condensed consolidated financial statements prior to that date. References to “Successor” relate to the reorganized Company’s financial position and results of operations as of and subsequent to the Emergence Date. References to “Predecessor” relate to the Company’s financial position prior to, and results of operations through and including, the Emergence Date.
Risks and Uncertainties	Risks and Uncertainties As a crude oil and natural gas producer, the Company’s revenue, profitability and future growth are substantially dependent upon the prevailing and future prices for crude oil and natural gas, which are dependent upon numerous factors beyond its control such as economic, political and regulatory developments and competition from other energy sources. The energy markets have historically been very volatile, and there can be no assurance that crude oil and natural gas prices will not be subject to wide fluctuations in the future. A substantial or extended decline in prices for crude oil and, to a lesser extent, natural gas and natural gas liquids (“NGLs”), could have a material adverse effect on the Company’s financial position, results of operations, cash flows, the quantities of crude oil and natural gas reserves that may be economically produced and the Company’s access to capital.
Cash Equivalents and Restricted Cash	Cash Equivalents and Restricted Cash The Company may invest in certain money market funds, commercial paper and time deposits, all of which are stated at fair value or cost which approximates fair value due to the short-term maturity of these investments. The Company classifies all such investments with original maturity dates less than 90 days as cash equivalents. As of September 30, 2021, restricted cash consisted of proceeds from the Oasis Senior Notes (defined in Note 11 – Long-Term Debt) held in a standalone account to fund a portion of the Williston Basin Acquisition (defined in Note 9 – Acquisitions). As of December 31, 2020, restricted cash consisted of funds that were held in an escrow account for the payment of professional fees associated with the Company’s emergence from bankruptcy.
Recent Accounting Pronouncements	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”). ASU 2020-04 provides optional guidance for a limited time to ease the potential burden in accounting for reference rate reform, including optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. ASU 2020-04 applies only to contracts and hedging relationships that reference the London Interbank Offered Rate (“LIBOR”) or another reference rate expected to be discontinued due to reference rate reform. ASU 2020-04 is effective immediately and may be applied prospectively to contract modifications made and hedging relationships entered into or evaluated on or before December 31, 2022. The Company is currently evaluating its contracts and the optional expedients provided by ASU 2020-04 and the impact the new standard will have on its financial statements and related disclosures.
Revenue Recognition	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 Company 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 Company does not recognize contract assets or contract liabilities under its customer contracts for which invoicing occurs once the Company’s performance obligations have been satisfied and payment is unconditional. Contract balances are classified as current or long-term based on when the Company expects to receive cash for contract assets or recognize revenue for contract liabilities. Contract liabilities are included in other current liabilities and other liabilities on the Company’s Condensed Consolidated Balance Sheets. There were no material contract asset balances at September 30, 2021 or December 31, 2020. Performance Obligations The Company records revenue when the performance obligations under the terms of its customer contracts are satisfied. For sales of commodities, the Company records revenue in the month the production or purchased product is delivered to the purchaser. However, settlement statements and payments are typically not received for 20 to 60 days after the date production is delivered, and as a result, the Company is required to estimate the amount of production that was delivered to the purchaser and the price that will be received for the sale of the product. The Company uses knowledge of its properties, its properties’ historical performance, spot market prices and other factors as the basis for these estimates. The Company records the differences between estimates and the actual amounts received for product sales once payment is received from the purchaser. For midstream services, the Company measures the satisfaction of its performance obligations using the output method based upon the volume of crude oil, natural gas or water that flows through its systems. In certain cases, the Company 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. Differences between estimated and actual revenues have historically not been significant. For the three and nine months ended September 30, 2021 and 2020, revenue recognized related to performance obligations satisfied in prior reporting periods was not material. The Company has elected practical expedients, pursuant to Accounting Standards Codification 606, Revenue from Contracts with Customers
Inventory	Inventory, including long-term inventory, is stated at the lower of cost and net realizable value with cost determined on an average cost method. The Company assesses the carrying value of inventory and uses estimates and judgment when making any adjustments necessary to reduce the carrying value to net realizable value. Among the uncertainties that impact the Company’s estimates are the applicable quality and location differentials to include in the Company’s net realizable value analysis as well as the liquidation timing of the inventory. Changes in assumptions made as to the timing of a sale can materially impact net realizable value.
Fair value measurement	In accordance with the FASB’s authoritative guidance on fair value measurements, the Company’s financial assets and liabilities are measured at fair value on a recurring basis. The Company’s financial instruments, including certain cash and cash equivalents, accounts receivable, accounts payable and other payables, are carried at cost, which approximates their respective fair market values due to their short-term maturities. The Company recognizes its non-financial assets and liabilities, such as asset retirement obligations (“ARO”) and properties acquired in a business combination or upon impairment, at fair value on a non-recurring basis. As defined in the authoritative guidance, fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). To estimate fair value, the Company utilizes market data or assumptions that market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs can be readily observable, market corroborated or generally unobservable. The authoritative guidance establishes a fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (“Level 1” measurements) and the lowest priority to unobservable inputs (“Level 3” measurements). The three levels of the fair value hierarchy are as follows: Level 1 — Unadjusted quoted prices are available in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2 — Pricing inputs, other than unadjusted quoted prices in active markets included in Level 1, are either directly or indirectly observable as of the reporting date. Level 2 includes those financial instruments that are valued using models or other valuation methodologies. These models are primarily industry-standard models that consider various assumptions, including quoted forward prices for commodities, time value, volatility factors and current market and contractual prices for the underlying instruments, as well as other relevant economic measures. Substantially all of these assumptions are observable in the marketplace throughout the full term of the instrument and can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace. Level 3 — Pricing inputs are generally unobservable from objective sources, requiring internally developed valuation methodologies that result in management’s best estimate of fair value. Financial Assets and Liabilities The fair value of the Company’s non-financial assets measured at fair value on a non-recurring basis is determined using valuation techniques that include Level 3 inputs. Asset retirement obligations. The initial measurement of ARO at fair value is recorded in the period in which the liability is incurred. Fair value is determined by calculating the present value of estimated future cash flows related to the liability. Estimating the future ARO requires management to make estimates and judgments regarding the timing and existence of a liability, as well as what constitutes adequate restoration when considering current regulatory requirements. Inherent in the fair value calculation are numerous assumptions and judgments, including the ultimate costs, inflation factors, credit-adjusted discount rates, timing of settlement and changes in the legal, regulatory, environmental and political environments.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Schedule of Cash and Cash Equivalents	The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Condensed Consolidated Balance Sheets and Condensed Consolidated Statements of Cash Flows: Successor September 30, 2021 December 31, 2020 (In thousands) Cash and cash equivalents $ 448,608 $ 15,856 Restricted cash — 4,370 Restricted cash – non–current 400,000 — Total cash, cash equivalents and restricted cash $ 848,608 $ 20,226

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	E&P revenues from contracts with customers for crude oil, natural gas and NGL sales and other services were as follows for the periods presented (in thousands): Successor Predecessor Successor Predecessor Three Months Ended September 30, 2021 Three Months Ended September 30, 2020 Nine Months Ended September 30, 2021 Nine Months Ended September 30, 2020 Crude oil revenues $ 205,731 $ 155,052 $ 598,278 $ 448,904 Purchased crude oil sales 53,562 35,442 163,785 144,719 Natural gas revenues 75,905 24,525 184,046 63,631 Purchased natural gas sales 8 308 362 4,909 Other services revenues 121 309 542 6,686 Total E&P revenues $ 335,327 $ 215,636 $ 947,013 $ 668,849 Revenues derived from contracts with customers for midstream revenues were as follows for the periods presented (in thousands): Successor Predecessor Successor Predecessor Three Months Ended September 30, 2021 Three Months Ended September 30, 2020 Nine Months Ended September 30, 2021 Nine Months Ended September 30, 2020 Midstream service revenues Crude oil, natural gas and NGL revenues $ 22,111 $ 22,682 $ 65,225 $ 72,267 Produced and flowback water revenues 10,312 8,801 25,230 27,300 Total midstream service revenues 32,423 31,483 90,455 99,567 Midstream product revenues Purchased crude oil sales (1) — 8,444 $ 19,738 $ 18,196 Crude oil, natural gas and NGL revenues 33,845 15,100 91,671 35,707 Freshwater revenues 444 396 1,681 2,890 Total midstream product revenues 34,289 23,940 113,090 56,793 Total midstream revenues $ 66,712 $ 55,423 $ 203,545 $ 156,360 ___________________ (1) Reported under purchased oil and gas sales on the Condensed Consolidated Statements of Operations.
Changes in Company's Contract Assets and Contract Liabilities	The following table summarizes the changes in the Company’s contract liabilities for the nine months ended September 30, 2021: (In thousands) Balance as of December 31, 2020 (Successor) $ 3,966 Cash received 3,231 Revenues recognized (276) Balance as of September 30, 2021 (Successor) $ 6,921
Remaining Performance Obligation Expected Satisfaction Period	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 (Successor): (In thousands) 2021 (excluding the nine months ended September 30, 2021) $ 3,709 2022 17,175 2023 10,896 2024 11,089 2025 2,768 Total $ 45,637

Inventory (Tables)

Inventory (Tables)	9 Months Ended
	Sep. 30, 2021
Inventory Disclosure [Abstract]
Components of Inventory	The Company’s total inventory consists of the following: Successor September 30, 2021 December 31, 2020 (In thousands) Inventory Equipment and materials $ 19,563 $ 25,103 Crude oil inventory 8,746 8,826 Total inventory 28,309 33,929 Long-term inventory Linefill in third party pipelines 17,510 14,522 Total long-term inventory 17,510 14,522 Total $ 45,819 $ 48,451
Components of Long-term Inventory	The Company’s total inventory consists of the following: Successor September 30, 2021 December 31, 2020 (In thousands) Inventory Equipment and materials $ 19,563 $ 25,103 Crude oil inventory 8,746 8,826 Total inventory 28,309 33,929 Long-term inventory Linefill in third party pipelines 17,510 14,522 Total long-term inventory 17,510 14,522 Total $ 45,819 $ 48,451

Additional Balance Sheet Info_2

Additional Balance Sheet Information (Tables)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Components of Balance Sheet Amounts	The following table sets forth certain balance sheet amounts comprised of the following: Successor September 30, 2021 December 31, 2020 (In thousands) Accounts receivable, net Trade accounts $ 200,301 $ 161,519 Joint interest accounts 39,291 31,920 Other accounts 31,560 13,206 Total accounts receivable 271,152 206,645 Less: allowance for credit losses (1,412) (106) Total accounts receivable, net $ 269,740 $ 206,539 Accrued liabilities Accrued capital costs $ 51,086 $ 39,380 Accrued lease operating expenses 15,257 18,635 Accrued oil and gas purchases 10,467 8,967 Accrued general and administrative expenses 9,964 35,249 Accrued dividends payable 4,224 — Accrued midstream operating expenses 21,933 15,051 Other accrued liabilities 16,069 9,002 Total accrued liabilities $ 129,000 $ 126,284

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Hierarchy of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables set forth by level, within the fair value hierarchy, the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis: Successor Fair value at September 30, 2021 Level 1 Level 2 Level 3 Total (In thousands) Assets: Permian Basin Sale Contingent Consideration $ — $ 39,717 $ — $ 39,717 Total assets $ — $ 39,717 $ — $ 39,717 Liabilities: Commodity derivative instruments $ — $ 408,853 $ — $ 408,853 Total liabilities $ — $ 408,853 $ — $ 408,853 Successor Fair value at December 31, 2020 Level 1 Level 2 Level 3 Total (In thousands) Assets: Commodity derivative instruments $ — $ 467 $ — $ 467 Total assets $ — $ 467 $ — $ 467 Liabilities: Commodity derivative instruments $ — $ 94,558 $ — $ 94,558 Total liabilities $ — $ 94,558 $ — $ 94,558

Derivative Instruments (Tables)

Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Outstanding Commodity Derivative Instruments	At September 30, 2021 (Successor), the Company had the following outstanding commodity derivative instruments: Commodity Settlement Derivative Volumes Weighted Average Prices Fair Value Assets (Liabilities) Fixed Price Swaps Floor Ceiling (In thousands) Crude oil 2021 Fixed price swaps 2,639,000 Bbl $ 42.09 $ (83,180) Crude oil 2021 Two-way collar 728,000 Bbl $ 51.25 $ 68.24 (4,343) Crude oil 2022 Fixed price swaps 7,245,000 Bbl $ 49.02 (155,383) Crude oil 2022 Two-way collar 4,799,000 Bbl $ 49.50 $ 66.62 (38,493) Crude oil 2023 Fixed price swaps 5,265,000 Bbl $ 50.00 (73,146) Crude oil 2023 Two-way collar 4,380,000 Bbl $ 45.42 $ 65.05 (25,702) Crude oil 2024 Fixed price swaps 434,000 Bbl $ 50.00 (4,811) Crude oil 2024 Two-way collar 372,000 Bbl $ 45.00 $ 64.88 (1,586) Natural gas 2021 Fixed price swaps 3,680,000 MMBtu $ 2.84 (11,222) Natural gas 2022 Fixed price swaps 5,430,000 MMBtu $ 2.82 (10,987) $ (408,853)
Gains and Losses from Commodity Derivative Instruments	The following table summarizes the location and amounts of gains and losses from the Company’s derivative instruments recorded in the Company’s Condensed Consolidated Statements of Operations for the periods presented (in thousands): Successor Predecessor Successor Predecessor Three Months Ended September 30, 2021 Three Months Ended September 30, 2020 Nine Months Ended September 30, 2021 Nine Months Ended September 30, 2020 Derivative Instrument Statements of Operations Location Commodity derivative instruments Net gain (loss) on derivative instruments $ (108,647) $ (5,071) $ (557,199) $ 243,064 Contingent consideration Net gain on derivative instruments 6,857 — 6,857 — Contingent consideration Gain on sale of properties — — 32,860 —
Summary of Gross and Net Information about Commodity Derivative Assets	The following table summarizes the location and fair value of all outstanding derivative instruments recorded in the Company’s Condensed Consolidated Balance Sheets: Successor September 30, 2021 Derivative Instrument Balance Sheet Location Gross Amount Gross Amount Offset Net Amount (In thousands) Derivatives assets: Contingent consideration Derivative instruments — non-current assets $ 39,717 $ — $ 39,717 Derivatives liabilities: Commodity contracts Derivative instruments — current liabilities $ 271,077 $ (4,740) $ 266,337 Commodity contracts Derivative instruments — non-current liabilities 164,614 (22,098) 142,516 Total derivatives liabilities $ 435,691 $ (26,838) $ 408,853 Successor December 31, 2020 Derivative Instrument Balance Sheet Location Gross Amount Gross Amount Offset Net Amount (In thousands) Derivatives assets: Commodity contracts Derivative instruments — current assets $ 467 $ — $ 467 Derivatives liabilities: Commodity contracts Derivative instruments — current liabilities $ 59,262 $ (2,318) $ 56,944 Commodity contracts Derivative instruments — non-current liabilities 38,426 (812) 37,614 Total derivatives liabilities $ 97,688 $ (3,130) $ 94,558
Summary of Gross and Net Information about Commodity Derivative Liabilities	The following table summarizes the location and fair value of all outstanding derivative instruments recorded in the Company’s Condensed Consolidated Balance Sheets: Successor September 30, 2021 Derivative Instrument Balance Sheet Location Gross Amount Gross Amount Offset Net Amount (In thousands) Derivatives assets: Contingent consideration Derivative instruments — non-current assets $ 39,717 $ — $ 39,717 Derivatives liabilities: Commodity contracts Derivative instruments — current liabilities $ 271,077 $ (4,740) $ 266,337 Commodity contracts Derivative instruments — non-current liabilities 164,614 (22,098) 142,516 Total derivatives liabilities $ 435,691 $ (26,838) $ 408,853 Successor December 31, 2020 Derivative Instrument Balance Sheet Location Gross Amount Gross Amount Offset Net Amount (In thousands) Derivatives assets: Commodity contracts Derivative instruments — current assets $ 467 $ — $ 467 Derivatives liabilities: Commodity contracts Derivative instruments — current liabilities $ 59,262 $ (2,318) $ 56,944 Commodity contracts Derivative instruments — non-current liabilities 38,426 (812) 37,614 Total derivatives liabilities $ 97,688 $ (3,130) $ 94,558

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	The following table sets forth the Company’s property, plant and equipment: Successor September 30, 2021 December 31, 2020 (In thousands) Proved oil and gas properties $ 731,292 $ 770,117 Less: Accumulated depreciation, depletion and amortization (70,343) (12,403) Proved oil and gas properties, net 660,949 757,714 Unproved oil and gas properties 2,293 40,211 Other property and equipment 962,174 935,950 Less: Accumulated depreciation (42,572) (5,088) Other property and equipment, net 919,602 930,862 Total property, plant and equipment, net $ 1,582,844 $ 1,728,787

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Schedule of Long-Term Debt	The Company’s long-term debt consists of the following: Successor September 30, 2021 December 31, 2020 (In thousands) Oasis Credit Facility $ — $ 260,000 Oasis Senior Notes 400,000 — Less: unamortized deferred financing costs on Oasis Senior Notes (8,495) — Total Oasis Guarantors 391,505 260,000 OMP Credit Facility 210,000 450,000 OMP Senior Notes 450,000 — Less: unamortized deferred financing costs on OMP Senior Notes (9,610) — Total unrestricted subsidiaries 650,390 450,000 Total long-term debt, net $ 1,041,895 $ 710,000

Asset Retirement Obligations (T

Asset Retirement Obligations (Tables)	9 Months Ended
	Sep. 30, 2021
Asset Retirement Obligation Disclosure [Abstract]
Schedule of Changes in Asset Retirement Obligations	The following table reflects the changes in the Company’s ARO during the nine months ended September 30, 2021: (In thousands) Balance at December 31, 2020 (Successor) $ 48,594 Liabilities incurred during period 409 Liabilities settled during period (322) Accretion expense during period 3,016 Revisions to estimates 194 Liabilities settled through divestitures (4,844) Balance at September 30, 2021 (Successor) $ 47,047

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Summary of Stock Based Compensation Assumptions	The following table summarizes the assumptions used in the Monte Carlo simulation model to determine the grant date fair value and associated equity-based compensation expenses by grant date: Grant date January 18, 2021 February 11, 2021 April 13, 2021 Forecast period (years) 3 - 4 3 - 4 3 - 4 Risk-free interest rates 0.2% - 0.3% 0.2% - 0.3% 0.3% - 0.6% Implied equity volatility 55% - 60% 55% - 60% 45% - 50% Stock price on date of grant $44.41 $49.66 $68.07

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Schedule of Weighted-Average Number of Shares Outstanding	The following table summarizes the basic and diluted weighted average common shares outstanding and the weighted average common shares excluded from the calculation of diluted weighted average common shares outstanding due to the anti-dilutive effect for the periods presented (in thousands): Successor Predecessor Successor Predecessor Three Months Ended September 30, 2021 Three Months Ended September 30, 2020 Nine Months Ended September 30, 2021 Nine Months Ended September 30, 2020 Weighted average common shares outstanding: Basic 19,812 318,287 19,905 317,365 Dilutive effect of equity-classified awards 956 — 603 — Dilutive effect of warrants 18 — — — Diluted 20,786 318,287 20,508 317,365 Anti-dilutive weighted average common shares: Potential common shares 2,152 4,292 2,295 7,420

Business Segment Information (T

Business Segment Information (Tables)	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Summarized Financial Information of Segments	The following table summarizes financial information for the Company’s two business segments for the periods presented: E&P Midstream Eliminations Consolidated (In thousands) Successor Three months ended September 30, 2021: Revenues from non-affiliates $ 335,327 $ 66,712 $ — $ 402,039 Inter-segment revenues — 41,561 (41,561) — Total revenues 335,327 108,273 (41,561) 402,039 Operating income 153,125 51,289 (824) 203,590 Total other expense, net (109,085) (11,173) — (120,258) Income before income taxes $ 44,040 $ 40,116 $ (824) $ 83,332 Lease operating expenses $ 44,914 $ — $ (15,607) $ 29,307 Gathering, processing and transportation expenses 30,028 — (13,628) 16,400 General and administrative expenses (1) 15,702 6,668 (2,856) 19,514 Equity-based compensation expenses 4,144 143 — 4,287 Predecessor Three months ended September 30, 2020: Revenues from non-affiliates $ 215,636 $ 55,423 $ — $ 271,059 Inter-segment revenues — 54,638 (54,638) — Total revenues 215,636 110,061 (54,638) 271,059 Operating income (loss) (8,603) 48,132 (1,005) 38,524 Total other expense, net (87,953) (2,812) — (90,765) Income (loss) before income taxes $ (96,556) $ 45,320 $ (1,005) $ (52,241) Lease operating expenses $ 41,235 $ — $ (11,882) $ 29,353 Gathering, processing and transportation expenses 32,003 — (11,675) 20,328 General and administrative expenses (1) 44,088 9,089 (3,926) 49,251 Equity-based compensation expenses 4,502 400 (68) 4,834 Successor Nine months ended September 30, 2021: Revenues from non-affiliates $ 947,013 $ 203,545 $ — $ 1,150,558 Inter-segment revenues — 125,007 (125,007) — Total revenues 947,013 328,552 (125,007) 1,150,558 Operating income (loss) 593,493 139,946 (3,441) 729,998 Total other income (expense), net (574,583) (26,039) — (600,622) Income before income taxes $ 18,910 $ 113,907 $ (3,441) $ 129,376 Lease operating expenses $ 146,414 $ — $ (47,526) $ 98,888 Gathering, processing and transportation expenses 90,920 — (38,324) 52,596 General and administrative expenses (1) 47,084 23,403 (10,026) 60,461 Equity-based compensation expenses 10,518 669 — 11,187 Predecessor Nine months ended September 30, 2020: Revenues from non-affiliates $ 668,849 $ 156,360 $ — $ 825,209 Inter-segment revenues — 160,377 (160,377) — Total revenues 668,849 316,737 (160,377) 825,209 Operating income (loss) (4,866,759) 36,526 (4,995) (4,835,228) Total other income (expense), net 140,580 (38,568) — 102,012 Loss before income taxes $ (4,726,179) $ (2,042) $ (4,995) $ (4,733,216) Lease operating expenses $ 144,912 $ — $ (36,182) $ 108,730 Gathering, processing and transportation expenses 105,897 — (32,340) 73,557 General and administrative expenses (1) 103,051 26,995 (12,178) 117,868 Equity-based compensation expenses 15,909 1,031 (409) 16,531 Successor At September 30, 2021: Property, plant and equipment, net $ 692,271 $ 893,333 $ (2,760) $ 1,582,844 Total assets 1,939,695 1,062,577 (2,760) 2,999,512 At December 31, 2020: Property, plant and equipment, net $ 837,020 $ 892,043 $ (276) $ 1,728,787 Total assets 1,093,253 1,066,060 (276) 2,159,037 ___________________ (1) Includes equity-based compensation expenses.

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Consolidation and Midstream Simplification (Details) - USD ($) $ in Millions	Mar. 30, 2021	Sep. 30, 2021
Simplification Transaction | OMP
Related Party Transaction [Line Items]
Consideration contributed	$ 512.5
Cumulative cash distributions	$ 231.5
Ownership interest (in shares)	12,949,644
Units converted (in shares)	1,850,356
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]
Parent ownership interest		70.00%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Cash and cash equivalents	$ 448,608	$ 15,856
Restricted cash	0	4,370
Restricted cash – non–current	400,000	0
Total cash, cash equivalents and restricted cash	$ 848,608	$ 20,226	$ 84,265	$ 20,019

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregated 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	$ 402,039	$ 271,059	$ 1,150,558	$ 825,209
E&P
Disaggregation of Revenue [Line Items]
Total revenues	335,327	215,636	947,013	668,849
E&P | Crude oil revenues
Disaggregation of Revenue [Line Items]
Total revenues	205,731	155,052	598,278	448,904
E&P | Purchased crude oil sales
Disaggregation of Revenue [Line Items]
Total revenues	53,562	35,442	163,785	144,719
E&P | Natural gas revenues
Disaggregation of Revenue [Line Items]
Total revenues	75,905	24,525	184,046	63,631
E&P | Purchased natural gas sales
Disaggregation of Revenue [Line Items]
Total revenues	8	308	362	4,909
E&P | Other services revenues
Disaggregation of Revenue [Line Items]
Total revenues	121	309	542	6,686
Midstream Total
Disaggregation of Revenue [Line Items]
Total revenues	66,712	55,423	203,545	156,360
Midstream Total | Purchased crude oil sales
Disaggregation of Revenue [Line Items]
Total revenues	0	8,444	19,738	18,196
Midstream Total | Crude oil, natural gas and NGL revenues
Disaggregation of Revenue [Line Items]
Total revenues	22,111	22,682	65,225	72,267
Midstream Total | Produced and flowback water revenues
Disaggregation of Revenue [Line Items]
Total revenues	10,312	8,801	25,230	27,300
Midstream Total | Total midstream service revenues
Disaggregation of Revenue [Line Items]
Total revenues	32,423	31,483	90,455	99,567
Midstream Total | Crude oil, natural gas and NGL revenues
Disaggregation of Revenue [Line Items]
Total revenues	33,845	15,100	91,671	35,707
Midstream Total | Freshwater revenues
Disaggregation of Revenue [Line Items]
Total revenues	444	396	1,681	2,890
Midstream Total | Total midstream product revenues
Disaggregation of Revenue [Line Items]
Total revenues	$ 34,289	$ 23,940	$ 113,090	$ 56,793

Revenue Recognition - Changes i

Revenue Recognition - Changes in Company's Contract Liabilities (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Change in Contract with Customer, Liability [Roll Forward]
Balance as of December 31, 2020 (Successor)	$ 3,966
Cash received	3,231
Revenues recognized	(276)
Balance as of September 30, 2021 (Successor)	$ 6,921

Revenue Recognition - Remaining

Revenue Recognition - 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 performance obligations	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	$ 3,709
Expected satisfaction period	3 months
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	$ 17,175
Expected satisfaction period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 10,896
Expected satisfaction period	1 year
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	$ 11,089
Expected satisfaction period	1 year
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	$ 2,768
Expected satisfaction period	1 year

Inventory - Components of Inven

Inventory - Components of Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Inventory
Equipment and materials	$ 19,563	$ 25,103
Crude oil inventory	8,746	8,826
Total inventory	28,309	33,929
Long-term inventory
Linefill in third party pipelines	17,510	14,522
Total long-term inventory	17,510	14,522
Total	$ 45,819	$ 48,451

Inventory - Narrative (Details)

Inventory - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Inventory [Line Items]
Inventory write-down	$ 0		$ 0
Crude oil inventory
Inventory [Line Items]
Inventory write-down		$ 0		$ 7,200,000
Long-term linefill inventory
Inventory [Line Items]
Inventory write-down		0		1,300,000
Equipment and materials
Inventory [Line Items]
Inventory write-down		$ 600,000		$ 1,600,000

Additional Balance Sheet Info_3

Additional Balance Sheet Information (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, gross	$ 271,152	$ 206,645
Less: allowance for credit losses	(1,412)	(106)
Total accounts receivable, net	269,740	206,539
Accrued capital costs	51,086	39,380
Accrued lease operating expenses	15,257	18,635
Accrued oil and gas purchases	10,467	8,967
Accrued general and administrative expenses	9,964	35,249
Accrued dividends payable	4,224	0
Accrued midstream operating expenses	21,933	15,051
Other accrued liabilities	16,069	9,002
Total accrued liabilities	129,000	126,284
Trade accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, gross	200,301	161,519
Joint interest accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, gross	39,291	31,920
Other accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, gross	$ 31,560	$ 13,206

Fair Value Measurements - Hiera

Fair Value Measurements - Hierarchy of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - Recurring - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets:
Permian Basin Sale Contingent Consideration	$ 39,717
Commodity derivative instruments		$ 467
Total assets	39,717	467
Liabilities:
Commodity derivative instruments	408,853	94,558
Total liabilities	408,853	94,558
Level 1
Assets:
Permian Basin Sale Contingent Consideration	0
Commodity derivative instruments		0
Total assets	0	0
Liabilities:
Commodity derivative instruments	0	0
Total liabilities	0	0
Level 2
Assets:
Permian Basin Sale Contingent Consideration	39,717
Commodity derivative instruments		467
Total assets	39,717	467
Liabilities:
Commodity derivative instruments	408,853	94,558
Total liabilities	408,853	94,558
Level 3
Assets:
Permian Basin Sale Contingent Consideration	0
Commodity derivative instruments		0
Total assets	0	0
Liabilities:
Commodity derivative instruments	0	0
Total liabilities	$ 0	$ 0

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Derivative credit risk valuation adjustment, derivative liabilities	$ 8.7	$ 4.3

Derivative Instruments - Narrat

Derivative Instruments - Narrative (Details) bbl in Thousands, $ in Thousands	Jun. 29, 2021USD ($)	May 20, 2021USD ($)	May 17, 2021$ / bblbbl	Sep. 30, 2021USD ($)$ / bblbbl	Sep. 30, 2020USD ($)	Dec. 31, 2025USD ($)	Dec. 31, 2024USD ($)	Dec. 31, 2023USD ($)	May 16, 2021$ / bbl
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative modification | $				$ 82,419	$ 0
Divestitures | Primary Permian Basin Sale
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Proceeds from divestiture | $		$ 375,000
Contingent consideration, minimum average daily settlement price, requiring additional payment (in dollars per barrel) | $ / bbl				60
Contingent consideration, minimum average daily settlement price, terminating agreement (in dollars per barrel) | $ / bbl				45
Gain on sale of properties | $	$ 32,900
Contingent consideration | $				$ 39,700
Anticipated | Divestitures | Primary Permian Basin Sale
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Proceeds from divestiture | $						$ 25,000	$ 25,000	$ 25,000
NYMEX WTI | Crude oil | 2022 Fixed price swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Weighted average swap price (in dollars per barrel) | $ / bbl			50	49.02					40.72
Total notional amount of oil (in Bbls) | bbl			6,346	7,245
NYMEX WTI | Crude oil | 2023 Fixed price swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Weighted average swap price (in dollars per barrel) | $ / bbl			50	50					43.57
Total notional amount of oil (in Bbls) | bbl			5,265	5,265
NYMEX WTI | Crude oil | 2024 Fixed price swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Weighted average swap price (in dollars per barrel) | $ / bbl			50	50					43.68
Total notional amount of oil (in Bbls) | bbl			434	434

Derivative Instruments - Schedu

Derivative Instruments - Schedule of Outstanding Commodity Derivative Instruments (Details) bbl in Thousands, BTU in Thousands, $ in Thousands	May 17, 2021$ / bblbbl	Sep. 30, 2021USD ($)BTU$ / bblbbl	May 16, 2021$ / bbl
Derivative [Line Items]
Fair Value Assets (Liabilities) | $		$ (408,853)
Crude oil | 2021 Fixed price swaps | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil (in Bbls) | bbl		2,639
Weighted average swap price (in dollars per barrel)		42.09
Fair Value Assets (Liabilities) | $		$ (83,180)
Crude oil | 2021 Two-way collar | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil (in Bbls) | bbl		728
Average floor price (in dollars per barrel)		51.25
Average ceiling price (in dollars per barrel)		68.24
Fair Value Assets (Liabilities) | $		$ (4,343)
Crude oil | 2022 Fixed price swaps | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil (in Bbls) | bbl	6,346	7,245
Weighted average swap price (in dollars per barrel)	50	49.02	40.72
Fair Value Assets (Liabilities) | $		$ (155,383)
Crude oil | 2022 Two Way collar | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil (in Bbls) | bbl		4,799
Average floor price (in dollars per barrel)		49.50
Average ceiling price (in dollars per barrel)		66.62
Fair Value Assets (Liabilities) | $		$ (38,493)
Crude oil | 2023 Fixed price swaps | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil (in Bbls) | bbl	5,265	5,265
Weighted average swap price (in dollars per barrel)	50	50	43.57
Fair Value Assets (Liabilities) | $		$ (73,146)
Crude oil | 2023 Two Way Collar | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil (in Bbls) | bbl		4,380
Average floor price (in dollars per barrel)		45.42
Average ceiling price (in dollars per barrel)		65.05
Fair Value Assets (Liabilities) | $		$ (25,702)
Crude oil | 2024 Fixed price swaps | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil (in Bbls) | bbl	434	434
Weighted average swap price (in dollars per barrel)	50	50	43.68
Fair Value Assets (Liabilities) | $		$ (4,811)
Crude oil | 2024 Two Way Collar | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil (in Bbls) | bbl		372
Average floor price (in dollars per barrel)		45
Average ceiling price (in dollars per barrel)		64.88
Fair Value Assets (Liabilities) | $		$ (1,586)
Natural gas | 2021 Fixed price swaps | NYMEX HH
Derivative [Line Items]
Total notional amount of natural gas (in MMBtu) | BTU		3,680
Weighted average swap price (in dollars per barrel)		2.84
Fair Value Assets (Liabilities) | $		$ (11,222)
Natural gas | 2022 Fixed price swaps | NYMEX HH
Derivative [Line Items]
Total notional amount of natural gas (in MMBtu) | BTU		5,430
Weighted average swap price (in dollars per barrel)		2.82
Fair Value Assets (Liabilities) | $		$ (10,987)

Derivative Instruments - Realiz

Derivative Instruments - Realized and Unrealized Gains and Losses from Commodity Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative [Line Items]
Net gain (loss) on derivative instruments	$ (101,790)	$ (5,071)	$ (550,342)	$ 243,064
Contingent consideration
Derivative [Line Items]
Net gain (loss) on derivative instruments	6,857	0	6,857	0
Gain on sale of properties	0	0	32,860	0
Commodity contracts
Derivative [Line Items]
Net gain (loss) on derivative instruments	$ (108,647)	$ (5,071)	$ (557,199)	$ 243,064

Derivative Instruments - Sche_2

Derivative Instruments - Schedule of Location and Fair Value of Outstanding Commodity Derivative Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Contingent consideration | Derivative instruments — non-current assets
Derivatives, Fair Value [Line Items]
Derivative asset, gross amounts recognized	$ 39,717
Derivative asset, gross amounts offset	0
Derivative asset, net asset	39,717
Commodity contracts
Derivatives, Fair Value [Line Items]
Derivative liability, gross amount recognized	435,691	$ 97,688
Derivative liability, gross amounts offset	(26,838)	(3,130)
Derivative liability, net liability	408,853	94,558
Commodity contracts | Derivative instruments — current assets
Derivatives, Fair Value [Line Items]
Derivative asset, gross amounts recognized		467
Derivative asset, gross amounts offset		0
Derivative asset, net asset		467
Commodity contracts | Derivative instruments — current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, gross amount recognized	271,077	59,262
Derivative liability, gross amounts offset	(4,740)	(2,318)
Derivative liability, net liability	266,337	56,944
Commodity contracts | Derivative instruments — non-current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, gross amount recognized	164,614	38,426
Derivative liability, gross amounts offset	(22,098)	(812)
Derivative liability, net liability	$ 142,516	$ 37,614

Property, Plant and Equipment_2

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Proved oil and gas properties	$ 731,292	$ 770,117
Less: Accumulated depreciation, depletion and amortization	(70,343)	(12,403)
Proved oil and gas properties, net	660,949	757,714
Unproved oil and gas properties	2,293	40,211
Other property and equipment	962,174	935,950
Less: Accumulated depreciation	(42,572)	(5,088)
Other property and equipment, net	919,602	930,862
Total property, plant and equipment, net	$ 1,582,844	$ 1,728,787

Acquisitions (Details)

Acquisitions (Details) - 2021 Williston Acquisition a in Thousands, $ in Millions	Oct. 21, 2021USD ($)	May 03, 2021USD ($)a	Apr. 01, 2021USD ($)
Asset Acquisition [Line Items]
Acres acquired | a		95
Purchase price		$ 585.8	$ 745
Cash paid		$ 74.5
Subsequent Event
Asset Acquisition [Line Items]
Cash paid	$ 511.3

Divestitures (Details)

Divestitures (Details) $ in Thousands	Jun. 29, 2021USD ($)	May 20, 2021USD ($)	Mar. 22, 2021USD ($)	Sep. 30, 2021USD ($)$ / bbl	Jun. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)$ / bbl	Sep. 30, 2020USD ($)	Dec. 31, 2025USD ($)	Dec. 31, 2024USD ($)	Dec. 31, 2023USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income before income taxes				$ 83,332		$ (52,241)	$ 129,376	$ (4,733,216)
Divestitures | Permian Basin Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture, net of adjustments					$ 24,000
Gain (loss) on divestiture				4,900			227,400
Income before income taxes				$ 5,900		$ 12,100	$ 268,100	$ (883,000)
Divestitures | Primary Permian Basin Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration transferred from divestiture		$ 450,000
Proceeds from divestiture		$ 375,000
Contingent consideration, minimum average daily settlement price, requiring additional payment (in dollars per barrel) | $ / bbl				60			60
Proceeds from divestiture, net of adjustments	$ 347,300
Divestitures | Primary Permian Basin Sale | Anticipated
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture									$ 25,000	$ 25,000	$ 25,000
Divestitures | Well Services Exit
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration transferred from divestiture			$ 5,500
Proceeds from divestiture			2,600
Divestitures | Well Services Exit | Promissory Note
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Promissory note			$ 2,900
Stated interest rate			6.60%

Long-Term Debt - Schedule of Lo

Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($)	Sep. 30, 2021	Jun. 09, 2021	Mar. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total long-term debt, net	$ 1,041,895,000			$ 710,000,000
Credit Facility | OMP Credit Facility
Debt Instrument [Line Items]
Total long-term debt, net	210,000,000
Senior Notes | Oasis Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross		$ 400,000,000
Less: unamortized deferred financing costs on Senior Notes		$ (9,000,000)
Senior Notes | OMP Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross			$ 450,000,000
Less: unamortized deferred financing costs on Senior Notes			$ (10,200,000)
Oasis Guarantors
Debt Instrument [Line Items]
Total long-term debt, net	391,505,000			260,000,000
Oasis Guarantors | Credit Facility | Oasis Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	0			260,000,000
Oasis Guarantors | Senior Notes | Oasis Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	400,000,000			0
Less: unamortized deferred financing costs on Senior Notes	(8,495,000)			0
Oasis Midstream Partners, LP
Debt Instrument [Line Items]
Total long-term debt, net	650,390,000			450,000,000
Oasis Midstream Partners, LP | Credit Facility | OMP Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	210,000,000			450,000,000
Oasis Midstream Partners, LP | Senior Notes | OMP Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	450,000,000			0
Less: unamortized deferred financing costs on Senior Notes	$ (9,610,000)			$ 0

Long-Term Debt - Oasis Credit F

Long-Term Debt - Oasis Credit Facility (Details) - Credit Facility - USD ($)	May 21, 2021	Sep. 30, 2021	Oct. 21, 2021	Mar. 22, 2021	Mar. 21, 2021	Dec. 31, 2020
Oasis Credit Facility
Debt Instrument [Line Items]
Credit facility borrowing base				$ 500,000,000	$ 575,000,000
Line of credit facility, current borrowing capacity				$ 450,000,000	$ 575,000,000
Letters of credit outstanding		$ 1,300,000
Line of credit facility, remaining borrowing capacity		$ 398,700,000
Weighted average interest rate (percent)		4.20%
Oasis Credit Facility | Oasis Guarantors
Debt Instrument [Line Items]
Long-term debt, gross		$ 0				$ 260,000,000
Oasis Credit Facility, Fourth Agreement
Debt Instrument [Line Items]
Credit facility borrowing base	$ 550,000,000
Covenant terms, percentage of availability	25.00%
Covenant terms, maximum pro forma leverage ratio	1.5
Covenant terms, maximum pro forma leverage ratio, subject to default and availability	2
Covenant terms, minimum pro forma leverage ratio subject to default and availability	1.5
Oasis Credit Facility, Fourth Agreement | 2021 Williston Acquisition
Debt Instrument [Line Items]
Increase (decrease) in maximum borrowing capacity	$ 250,000,000
Oasis Credit Facility, Fourth Agreement | Primary Permian Basin Sale
Debt Instrument [Line Items]
Increase (decrease) in maximum borrowing capacity	$ (100,000,000)
Oasis Credit Facility, Fifth Agreement | 2021 Williston Acquisition | Subsequent Event
Debt Instrument [Line Items]
Credit facility borrowing base			$ 900,000,000
Elected commitments			$ 450,000,000
Minimum | LIBOR | Oasis Credit Facility
Debt Instrument [Line Items]
Stated interest rate				0.25%	1.00%

Long-Term Debt - Oasis Bridge F

Long-Term Debt - Oasis Bridge Facility (Details) - Senior Secured Lien - Senior Notes - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	May 03, 2021
Debt Instrument [Line Items]
Long-term debt, gross		$ 500
Aggregate fees	$ 7.8

Long-Term Debt - Oasis Senior N

Long-Term Debt - Oasis Senior Notes (Details) - USD ($) $ in Thousands	Jun. 09, 2021	Sep. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Proceeds from issuance of senior unsecured notes		$ 850,000	$ 0
Oasis Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 400,000
Stated interest rate	6.375%
Proceeds from issuance of senior unsecured notes	$ 393,000
Debt issuance costs	$ 9,000
Oasis Senior Notes | Senior Notes | Level 1
Debt Instrument [Line Items]
Long-term debt, fair value		$ 419,000

Long-Term Debt - OMP Credit Fac

Long-Term Debt - OMP Credit Facility (Details) - USD ($) $ in Thousands	Mar. 22, 2021	Sep. 30, 2021	Sep. 30, 2021	Mar. 21, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total long-term debt		$ 1,041,895	$ 1,041,895		$ 710,000
OMP Credit Facility | Credit Facility
Debt Instrument [Line Items]
Debt obligation, maximum consolidated total leverage ratio	500.00%
Debt obligation, maximum senior secured leverage ratio	300.00%
Debt obligation, maximum consolidated interest coverage ratio	250.00%
Credit facility borrowing base		450,000	450,000
Total long-term debt		210,000	210,000
Letters of credit outstanding		5,500	5,500
Line of credit facility, remaining borrowing capacity		$ 234,500	$ 234,500
Weighted average interest rate (percent)		2.50%	2.40%
OMP Credit Facility | Credit Facility | Minimum
Debt Instrument [Line Items]
Commitment fee percentage			0.375%
OMP Credit Facility | Credit Facility | Minimum | Eurodollar
Debt Instrument [Line Items]
Spread on variable rate (percent)			2.25%
OMP Credit Facility | Credit Facility | Minimum | Alternate Based Rate (ABR)
Debt Instrument [Line Items]
Spread on variable rate (percent)			1.25%
OMP Credit Facility | Credit Facility | Maximum
Debt Instrument [Line Items]
Commitment fee percentage			0.50%
OMP Credit Facility | Credit Facility | Maximum | Eurodollar
Debt Instrument [Line Items]
Spread on variable rate (percent)			3.25%
OMP Credit Facility | Credit Facility | Maximum | Alternate Based Rate (ABR)
Debt Instrument [Line Items]
Spread on variable rate (percent)			2.25%
OMP Senior Notes | Senior Notes
Debt Instrument [Line Items]
Line of credit facility, current borrowing capacity	$ 450,000			$ 575,000

Long-Term Debt - OMP Senior Not

Long-Term Debt - OMP Senior Notes (Details) - USD ($) $ in Thousands	Mar. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Proceeds from issuance of senior unsecured notes		$ 850,000	$ 0
Payments of other fees and expenses	$ 6,100
Simplification Transaction | OMS Holdings
Debt Instrument [Line Items]
Cumulative cash distributions	231,500
OMP Senior Notes | Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 450,000
Stated interest rate	8.00%
Proceeds from issuance of senior unsecured notes	$ 442,100
Debt issuance costs	10,200
OMP Senior Notes | Senior Notes | Level 1
Debt Instrument [Line Items]
Long-term debt, fair value		$ 468,000
OMP Credit Facility | Credit Facility
Debt Instrument [Line Items]
Repayments of lines of credit	204,000
Payments of accrued interest	$ 500

Asset Retirement Obligations -

Asset Retirement Obligations - Schedule of Changes in Asset Retirement Obligations (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of period	$ 48,594
Liabilities incurred during period	409
Liabilities settled during period	(322)
Accretion expense during period	3,016
Revisions to estimates	194
Liabilities settled through divestitures	(4,844)
Balance at end of period	$ 47,047

Asset Retirement Obligations _2

Asset Retirement Obligations - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Asset Retirement Obligation Disclosure [Abstract]
Total asset retirement obligations, current portion	$ 1.1	$ 2.2

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Effective tax rate (as percent)	0.00%		9.80%	0.00%	5.50%
Valuation allowance	$ 529.8			$ 529.8		$ 565.4
Decrease in valuation allowance				$ (35.6)
Payment of estimated income tax		$ 20

Equity-Based Compensation - Res

Equity-Based Compensation - Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses	$ 4,287	$ 4,834	$ 11,187	$ 16,531
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			25.00%
Award vesting period			4 years
Awards granted (in shares)			443,836
Granted, weighted average grant date fair value (dollars per share)			$ 51.64
Equity-based compensation expenses	$ 1,400		$ 3,500

Equity-Based Compensation - Per

Equity-Based Compensation - Performance Share Units (Details) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)$ / sharesshares	Sep. 30, 2020USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses	$ 4,287	$ 4,834	$ 11,187	$ 16,531
Company's Oil and Gas Peers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Eligible to be earned, percentage			0.50
Broad Based Russell 2000 Index
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Eligible to be earned, percentage			0.50
2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses		5,900		12,400
Performance Share Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses		$ 1,600		$ 5,700
Performance Share Unit Awards | 2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares) | shares			183,915
Weighted average grant date value (in dollars per share) | $ / shares			$ 63.95
Equity-based compensation expenses	$ 900		$ 2,200
Minimum | Performance Share Unit Awards | 2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years
PSU granted percentage of earnings (as a percent)			0.00%
Maximum | Performance Share Unit Awards | 2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			4 years
PSU granted percentage of earnings (as a percent)			150.00%

Equity-Based Compensation - Lev

Equity-Based Compensation - Leveraged Stock Units (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses	$ 4,287	$ 4,834	$ 11,187	$ 16,531
2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses		$ 5,900		$ 12,400
Leverage Stock Units | 2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)			262,406
Weighted average grant date value (in dollars per share)			$ 78.79
Equity-based compensation expenses	$ 1,600		$ 4,000
Minimum | Leverage Stock Units | 2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years
PSU granted percentage of earnings (as a percent)			0.00%
Maximum | Leverage Stock Units | 2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			4 years
PSU granted percentage of earnings (as a percent)			300.00%

Equity-Based Compensation - Sum

Equity-Based Compensation - Summary of Assumptions (Details) - Performance Share Units and Leveraged Stock Units - $ / shares	Apr. 13, 2021	Feb. 11, 2021	Jan. 18, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock price on date of grant (in dollars per share)	$ 68.07	$ 49.66	$ 44.41
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forecast period (years)	3 years	3 years	3 years
Risk-free interest rates	0.30%	0.20%	0.20%
Implied equity volatility	45.00%	55.00%	55.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forecast period (years)	4 years	4 years	4 years
Risk-free interest rates	0.60%	0.30%	0.30%
Implied equity volatility	50.00%	60.00%	60.00%

Equity-Based Compensation - Add

Equity-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	Mar. 30, 2023	Mar. 30, 2022	Mar. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses				$ 4,287	$ 4,834	$ 11,187	$ 16,531
2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses					5,900		12,400
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						3 years
Equity-based compensation expenses					3,100		10,600
Restricted Stock | 2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses				300		$ 900
Vesting percentage						33.33%
Class B Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						4 years
Equity-based compensation expenses				1,400		$ 3,500
Vesting percentage						25.00%
Class B Restricted Stock Units | Officers and Certain Other Senior Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			34.00%
Unamortized grant date value				400		$ 400
Cost not yet recognized, remaining term						2 years
Class B Restricted Stock Units | Officers and Certain Other Senior Employees | Anticipated
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%	33.00%
Performance Share Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses					$ 1,600		$ 5,700
Performance Share Unit Awards | 2020 Incentive Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expenses				$ 900		$ 2,200

Stockholders' Equity - Dividend

Stockholders' Equity - Dividends (Details) - USD ($)	Nov. 02, 2021	Oct. 26, 2021	Aug. 27, 2021	Aug. 03, 2021	Jul. 21, 2021	Jun. 29, 2021	May 31, 2021	May 03, 2021	Mar. 22, 2021	Feb. 24, 2021	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Jul. 12, 2021	Mar. 31, 2021
Dividends Payable [Line Items]
Dividends to shareholders (in usd per share)				$ 0.375				$ 0.375		$ 0.375
Dividends paid			$ 7,500,000		$ 80,000,000		$ 7,500,000		$ 7,500,000				$ 102,123,000	$ 0
Stock repurchase program, authorized amount																$ 100,000,000
Repurchase of common stock (in shares)													190,783
Treasury stock, acquired, average cost (in dollars per share)													$ 76.30
Treasury stock, value acquired												$ 14,560,000	$ 14,600,000
Warrants outstanding (in shares)											1,615,555		1,615,555
Warrants exercised (in shares)											2,791		6,050
Exercise price of warrants or rights (in usd per share)											$ 94.57		$ 94.57		$ 90.57
Subsequent Event
Dividends Payable [Line Items]
Dividends to shareholders (in usd per share)		$ 0.50
Repurchase of common stock (in shares)	156,519
Treasury stock, acquired, average cost (in dollars per share)	$ 121.22
Treasury stock, value acquired	$ 19,000,000
Special Cash Dividend
Dividends Payable [Line Items]
Dividends to shareholders (in usd per share)						$ 4						$ 4

Stockholders' Equity - OMP Equi

Stockholders' Equity - OMP Equity Offering (Details) - USD ($) $ / shares in Units, $ in Millions	Jun. 29, 2021	Sep. 30, 2021
Dividends Payable [Line Items]
Partners' capital account, units, redeemed (in shares)	3,623,188
Partners' capital account, redemptions	$ 87
Oasis Midstream Partners, LP
Dividends Payable [Line Items]
Parent ownership interest		70.00%
Noncontrolling interest ownership interest		30.00%
Public Stock Offering
Dividends Payable [Line Items]
Sale of stock, number of shares issued in transaction (in shares)	3,623,188
Sale of stock, price per share (in usd per share)	$ 24
Sale of stock, consideration received on transaction	$ 86.7

Stockholders' Equity - Tax Bene

Stockholders' Equity - Tax Benefit Provision Plan (Details)	Aug. 03, 2021
Equity [Abstract]
Share purchase right, convertible ratio	1
Share purchase right, term	3 years
Share purchase right, percentage of outstanding common shares acquired	4.95%

Earnings (Loss) Per Share (Deta

Earnings (Loss) Per Share (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 [Abstract]
Weighted average common shares outstanding, basic (in shares)	19,812	318,287	19,905	317,365
Weighted average common shares outstanding, dilutive effect of equity classified awards (in shares)	956	0	603	0
Weighted average common shares outstanding, dilutive effect of warrants (in shares)	18	0	0	0
Weighted average common stock shares outstanding, diluted (in shares)	20,786	318,287	20,508	317,365
Anti-dilutive weighted average common shares (in shares)	2,152	4,292	2,295	7,420

Business Segment Information (D

Business Segment Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)segment	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)
Segment Reporting [Abstract]
Number of current operating units | segment			2
Segment Reporting Information [Line Items]
Total revenues	$ 402,039	$ 271,059	$ 1,150,558	$ 825,209
Operating income (loss)	203,590	38,524	729,998	(4,835,228)
Total other income (expense), net	(120,258)	(90,765)	(600,622)	102,012
Income before income taxes	83,332	(52,241)	129,376	(4,733,216)
Lease operating expenses	29,307	29,353	98,888	108,730
Gathering, processing and transportation expenses	16,400	20,328	52,596	73,557
General and administrative expenses	19,514	49,251	60,461	117,868
Equity-based compensation expenses	4,287	4,834	11,187	16,531
Property, plant and equipment, net	1,582,844		1,582,844		$ 1,728,787
Total assets	2,999,512		2,999,512		2,159,037
E&P
Segment Reporting Information [Line Items]
Total revenues	335,327	215,636	947,013	668,849
Midstream Total
Segment Reporting Information [Line Items]
Total revenues	66,712	55,423	203,545	156,360
Operating Segments | E&P
Segment Reporting Information [Line Items]
Total revenues	335,327	215,636	947,013	668,849
Operating income (loss)	153,125	(8,603)	593,493	(4,866,759)
Total other income (expense), net	(109,085)	(87,953)	(574,583)	140,580
Income before income taxes	44,040	(96,556)	18,910	(4,726,179)
Lease operating expenses	44,914	41,235	146,414	144,912
Gathering, processing and transportation expenses	30,028	32,003	90,920	105,897
General and administrative expenses	15,702	44,088	47,084	103,051
Equity-based compensation expenses	4,144	4,502	10,518	15,909
Property, plant and equipment, net	692,271		692,271		837,020
Total assets	1,939,695		1,939,695		1,093,253
Operating Segments | Midstream Total
Segment Reporting Information [Line Items]
Total revenues	108,273	110,061	328,552	316,737
Operating income (loss)	51,289	48,132	139,946	36,526
Total other income (expense), net	(11,173)	(2,812)	(26,039)	(38,568)
Income before income taxes	40,116	45,320	113,907	(2,042)
Lease operating expenses	0	0	0	0
Gathering, processing and transportation expenses	0	0	0	0
General and administrative expenses	6,668	9,089	23,403	26,995
Equity-based compensation expenses	143	400	669	1,031
Property, plant and equipment, net	893,333		893,333		892,043
Total assets	1,062,577		1,062,577		1,066,060
Eliminations
Segment Reporting Information [Line Items]
Total revenues	(41,561)	(54,638)	(125,007)	(160,377)
Operating income (loss)	(824)	(1,005)	(3,441)	(4,995)
Total other income (expense), net	0	0	0	0
Income before income taxes	(824)	(1,005)	(3,441)	(4,995)
Lease operating expenses	(15,607)	(11,882)	(47,526)	(36,182)
Gathering, processing and transportation expenses	(13,628)	(11,675)	(38,324)	(32,340)
General and administrative expenses	(2,856)	(3,926)	(10,026)	(12,178)
Equity-based compensation expenses	0	(68)	0	(409)
Property, plant and equipment, net	(2,760)		(2,760)		(276)
Total assets	(2,760)		(2,760)		$ (276)
Eliminations | E&P
Segment Reporting Information [Line Items]
Total revenues	0	0	0	0
Eliminations | Midstream Total
Segment Reporting Information [Line Items]
Total revenues	$ (41,561)	$ (54,638)	$ (125,007)	$ (160,377)

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions	Nov. 19, 2020	Sep. 28, 2020	May 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Surety Bond
Commitments and Contingencies [Line Items]
Off-balance sheet commitments				$ 10.2
Revolving Credit Facility
Commitments and Contingencies [Line Items]
Off-balance sheet commitments				6.7
Settled | Mirada Litigation
Commitments and Contingencies [Line Items]
Amount proposed to be paid under Settlement Agreement		$ 42.8
Payments for legal settlements	$ 20		$ 22.8
Volume Commitment Agreement - Permian Basin Sale
Commitments and Contingencies [Line Items]
Other commitments					$ 32.6
Volume Commitment Agreement -Subsequent Oil and Gas Delivery Commitment
Commitments and Contingencies [Line Items]
Other commitments				$ 258.6
Other commitment, duration term				7 years

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event - OMP Merger $ in Millions	Oct. 25, 2021USD ($)shares
Crestwood Equity Partners LP
Subsequent Event [Line Items]
Ownership interest acquired	22.00%
Crestwood Equity Partners LP
Subsequent Event [Line Items]
Cash paid	$ 160
Aggregate consideration paid in shares (shares) | shares	21,000,000
Crestwood Equity Partners LP | Limited Partner
Subsequent Event [Line Items]
Cash paid	$ 150
Limited partners capital account, outstanding (in shares) | shares	6,520,944
Business acquisition, common shares, conversion ratio	76.80%
Crestwood Equity Partners LP | General Partner
Subsequent Event [Line Items]
Cash paid	$ 10
Business acquisition, common shares, conversion ratio	87.00%

Uncategorized Items - oas-20210

Label	Element	Value
Accounting Standards Update [Extensible Enumeration]	us-gaap_AccountingStandardsUpdateExtensibleList	Accounting Standards Update 2016-13 [Member]