Magnolia Oil & Gas (MGY) 10-Q 2 Nov 21 2021 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2021	Oct. 28, 2021
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-38083
Entity Registrant Name	Magnolia Oil & Gas Corp
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	81-5365682
Entity Address, Address Line One	Nine Greenway Plaza, Suite 1300
Entity Address, City or Town	Houston,
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77046
City Area Code	713
Local Phone Number	842-9050
Title of 12(b) Security	Class A Common Stock, par value $0.0001
Trading Symbol	MGY
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0001698990
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false
Class A Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		181,801,600
Class B Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		49,292,476

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
CURRENT ASSETS
Cash and cash equivalents	$ 245,023	$ 192,561
Accounts receivable	130,100	81,559
Drilling advances	63	3,805
Other current assets	1,567	3,601
Total current assets	376,753	281,526
PROPERTY, PLANT AND EQUIPMENT
Oil and natural gas properties	2,308,425	2,130,125
Other	6,799	4,412
Accumulated depreciation, depletion and amortization	(1,119,349)	(985,010)
Total property, plant and equipment, net	1,195,875	1,149,527
OTHER ASSETS
Deferred financing costs, net	4,291	6,042
Intangible assets, net	0	9,346
Other long-term assets	8,860	6,979
Total other assets	13,151	22,367
TOTAL ASSETS	1,585,779	1,453,420
CURRENT LIABILITIES
Accounts payable	107,460	62,626
Other current liabilities (Note 8)	83,225	66,323
Total current liabilities	190,685	128,949
LONG-TERM LIABILITIES
Long-term debt, net	387,537	391,115
Asset retirement obligations, net of current	96,062	88,232
Other long-term liabilities	5,978	5,702
Total long-term liabilities	489,577	485,049
COMMITMENTS AND CONTINGENCIES (Note 10)
Additional paid-in capital	1,665,805	1,712,544
Treasury Stock, at cost, 11,468 shares and 5,475 shares in 2021 and 2020, respectively	(112,796)	(38,958)
Accumulated deficit	(858,397)	(1,125,450)
Noncontrolling interest	210,881	291,260
Total equity	905,517	839,422
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	1,585,779	1,453,420
Class A Common Stock
Common stock	19	17
Class B Common Stock
Common stock	$ 5	$ 9

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Treasury stock (in shares)	11,468,000	5,475,000
Class A Common Stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	1,300,000,000	1,300,000,000
Common stock, shares issued (in shares)	189,627,000	168,755,000
Common stock, shares outstanding (in shares)	178,160,000	163,280,000
Class B Common Stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	225,000,000	225,000,000
Common stock, shares issued (in shares)	52,916,000	85,790,000
Common stock, shares outstanding (in shares)	52,916,000	85,790,000

Consolidated Statements of Oper

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	$ 283,579	$ 121,067	$ 741,968	$ 385,271
OPERATING EXPENSES
Lease operating expenses	23,593	18,802	64,957	61,275
Gathering, transportation and processing	10,077	5,771	27,839	20,579
Taxes other than income	14,082	7,331	38,657	22,874
Exploration expense	317	701	2,440	563,589
Impairment of oil and natural gas properties	0	0	0	1,381,258
Asset retirement obligations accretion	1,329	1,501	4,065	4,403
Depreciation, depletion and amortization	47,993	44,731	134,268	238,273
Amortization of intangible assets	0	3,626	9,346	10,879
General and administrative expenses	14,695	16,663	59,816	50,472
Total operating expenses	112,086	99,126	341,388	2,353,602
OPERATING INCOME (LOSS)	171,493	21,941	400,580	(1,968,331)
OTHER INCOME (EXPENSE)
Income from equity method investee	0	1,007	0	2,059
Interest expense, net	(7,474)	(7,333)	(23,519)	(21,345)
Loss on derivatives, net	(623)	(2,208)	(3,110)	(2,208)
Other income (expense), net	142	(51)	48	(510)
Total other expense, net	(7,955)	(8,585)	(26,581)	(22,004)
INCOME (LOSS) BEFORE INCOME TAXES	163,538	13,356	373,999	(1,990,335)
Income tax expense (benefit)	3,631	(339)	6,428	(79,340)
NET INCOME (LOSS)	159,907	13,695	367,571	(1,910,995)
LESS: Net income (loss) attributable to noncontrolling interest	40,543	4,548	100,518	(674,860)
NET INCOME (LOSS) ATTRIBUTABLE TO CLASS A COMMON STOCK	$ 119,364	$ 9,147	$ 267,053	$ (1,236,135)
WEIGHTED AVERAGE NUMBER OF COMMON SHARES OUTSTANDING
Basic (in shares)	174,764	166,467	172,281	166,728
Diluted (in shares)	175,683	170,676	173,280	166,728
Class A Common Stock
NET INCOME (LOSS) PER SHARE OF CLASS A COMMON STOCK
Basic (in dollars per share)	$ 0.68	$ 0.05	$ 1.54	$ (7.41)
Diluted (in dollars per share)	$ 0.67	$ 0.05	$ 1.53	$ (7.41)
Oil revenues
REVENUES
Total revenues	$ 195,132	$ 95,677	$ 529,641	$ 311,153
Natural gas revenues
REVENUES
Total revenues	42,828	14,895	110,187	44,238
Natural gas liquids revenues
REVENUES
Total revenues	$ 45,619	$ 10,495	$ 102,140	$ 29,880

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders’ Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Class A Common Stock	Class B Common Stock	Total Stockholders’ Equity	Total Stockholders’ EquityClass A Common Stock	Common StockClass A Common Stock	Common StockClass B Common Stock	Additional Paid In Capital	Additional Paid In CapitalClass B Common Stock	Treasury Stock	Treasury StockClass A Common Stock	Accumulated Deficit	Noncontrolling Interest	Noncontrolling InterestClass B Common Stock
Balance at beginning of period (in shares) at Dec. 31, 2019						168,319	85,790			1,000
Balance at beginning of period at Dec. 31, 2019	$ 2,728,529			$ 1,776,051		$ 17	$ 9	$ 1,703,362		$ (10,277)		$ 82,940	$ 952,478
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	2,879			1,902				1,902					977
Changes in ownership interest adjustment	0			(970)				(970)					970
Common stock issued related to stock based compensation and other, net (in shares)						154
Common stock issued related to stock based compensation and other, net	(452)			(298)				(298)					(154)
Class A Common Stock repurchases (in shares)											1,000
Class A Common Stock repurchases		$ (6,483)			$ (6,483)						$ (6,483)
Distributions to noncontrolling interest owners	(284)												(284)
Net income (loss)	(1,895,299)			(1,227,010)								(1,227,010)	(668,289)
Balance at end of period (in shares) at Mar. 31, 2020						168,473	85,790			2,000
Balance at end of period at Mar. 31, 2020	828,890			543,192		$ 17	$ 9	1,703,996		$ (16,760)		(1,144,070)	285,698
Balance at beginning of period (in shares) at Dec. 31, 2019						168,319	85,790			1,000
Balance at beginning of period at Dec. 31, 2019	2,728,529			1,776,051		$ 17	$ 9	1,703,362		$ (10,277)		82,940	952,478
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(1,910,995)
Balance at end of period (in shares) at Sep. 30, 2020						168,676	85,790			3,100
Balance at end of period at Sep. 30, 2020	812,181			532,634		$ 17	$ 9	1,709,043		$ (23,240)		(1,153,195)	279,547
Balance at beginning of period (in shares) at Mar. 31, 2020						168,473	85,790			2,000
Balance at beginning of period at Mar. 31, 2020	828,890			543,192		$ 17	$ 9	1,703,996		$ (16,760)		(1,144,070)	285,698
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	3,065			2,023				2,023					1,042
Changes in ownership interest adjustment	0			124				124					(124)
Common stock issued related to stock based compensation and other, net (in shares)						114
Common stock issued related to stock based compensation and other, net	(33)			(22)				(22)					(11)
Distributions to noncontrolling interest owners	(207)												(207)
Net income (loss)	(29,391)			(18,272)								(18,272)	(11,119)
Balance at end of period (in shares) at Jun. 30, 2020						168,587	85,790			2,000
Balance at end of period at Jun. 30, 2020	802,324			527,045		$ 17	$ 9	1,706,121		$ (16,760)		(1,162,342)	275,279
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	2,927			1,931				1,931					996
Changes in ownership interest adjustment	0			1,110				1,110					(1,110)
Common stock issued related to stock based compensation and other, net (in shares)						89
Common stock issued related to stock based compensation and other, net	(180)			(119)				(119)					(61)
Class A Common Stock repurchases (in shares)											1,100
Class A Common Stock repurchases		(6,480)			(6,480)						$ (6,480)
Distributions to noncontrolling interest owners	(105)												(105)
Net income (loss)	13,695			9,147								9,147	4,548
Balance at end of period (in shares) at Sep. 30, 2020						168,676	85,790			3,100
Balance at end of period at Sep. 30, 2020	812,181			532,634		$ 17	$ 9	1,709,043		$ (23,240)		(1,153,195)	279,547
Balance at beginning of period (in shares) at Dec. 31, 2020						168,755	85,790			5,475
Balance at beginning of period at Dec. 31, 2020	839,422			548,162		$ 17	$ 9	1,712,544		$ (38,958)		(1,125,450)	291,260
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	2,705			1,835				1,835					870
Changes in ownership interest adjustment	0			28,924				28,924					(28,924)
Common stock issued related to stock based compensation and other, net (in shares)						244
Common stock issued related to stock based compensation and other, net	(1,238)			(839)				(839)					(399)
Class A Common Stock repurchases (in shares)											1,973
Class A Common Stock repurchases		(20,281)			(20,281)						$ (20,281)
Class B Common Stock purchase and cancellation (in shares)							(5,000)
Class B Common Stock purchase and cancellation			$ (50,781)				$ (1)		$ 1					$ (50,781)
Non-compete settlement (in shares)						375
Non-compete settlement	(17,152)			(11,231)				(11,231)					(5,921)
Conversion of Class B Common Stock to Class A Common Stock (in shares)						14,166	(14,166)
Conversion of Class B Common Stock to Class A Common Stock	0					$ 1	$ (1)
Distributions to noncontrolling interest owners	(155)												(155)
Net income (loss)	91,492			63,244								63,244	28,248
Balance at end of period (in shares) at Mar. 31, 2021						183,540	66,624			7,448
Balance at end of period at Mar. 31, 2021	844,012			609,814		$ 18	$ 7	1,731,234		$ (59,239)		(1,062,206)	234,198
Balance at beginning of period (in shares) at Dec. 31, 2020						168,755	85,790			5,475
Balance at beginning of period at Dec. 31, 2020	839,422			548,162		$ 17	$ 9	1,712,544		$ (38,958)		(1,125,450)	291,260
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	367,571
Balance at end of period (in shares) at Sep. 30, 2021						189,627	52,916			11,468
Balance at end of period at Sep. 30, 2021	905,517			694,636		$ 19	$ 5	1,665,805		$ (112,796)		(858,397)	210,881
Balance at beginning of period (in shares) at Mar. 31, 2021						183,540	66,624			7,448
Balance at beginning of period at Mar. 31, 2021	844,012			609,814		$ 18	$ 7	1,731,234		$ (59,239)		(1,062,206)	234,198
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	3,528			2,577				2,577					951
Changes in ownership interest adjustment	0			(30,662)				(30,662)					30,662
Common stock issued related to stock based compensation and other, net (in shares)						160
Common stock issued related to stock based compensation and other, net	(61)			(44)				(44)					(17)
Class A Common Stock repurchases (in shares)											2,025
Class A Common Stock repurchases		(24,047)			(24,047)						$ (24,047)
Class B Common Stock purchase and cancellation (in shares)							(5,000)
Class B Common Stock purchase and cancellation			(71,750)				$ (1)		$ 1					(71,750)
Non-compete settlement	(24,922)			(18,527)				(18,527)					(6,395)
Conversion of Class B Common Stock to Class A Common Stock (in shares)						1,100	(1,100)
Distributions to noncontrolling interest owners	(276)												(276)
Net income (loss)	116,172			84,445								84,445	31,727
Balance at end of period (in shares) at Jun. 30, 2021						184,800	60,524			9,473
Balance at end of period at Jun. 30, 2021	842,656			623,556		$ 18	$ 6	1,684,579		$ (83,286)		(977,761)	219,100
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	2,910			2,180				2,180					730
Changes in ownership interest adjustment	0			(5,373)				(5,373)					5,373
Common stock issued related to stock based compensation and other, net (in shares)						219
Common stock issued related to stock based compensation and other, net	(1,797)			(1,348)				(1,348)					(449)
Class A Common Stock repurchases (in shares)											1,995
Class A Common Stock repurchases		$ (29,510)			$ (29,510)						$ (29,510)
Class B Common Stock purchase and cancellation (in shares)							(3,000)
Class B Common Stock purchase and cancellation			$ (49,140)											$ (49,140)
Conversion of Class B Common Stock to Class A Common Stock (in shares)						4,608	(4,608)
Conversion of Class B Common Stock to Class A Common Stock	0					$ 1	$ (1)
Dividends declared	(14,233)			(14,233)				(14,233)
Distributions to noncontrolling interest owners	(5,276)												(5,276)
Net income (loss)	159,907			119,364								119,364	40,543
Balance at end of period (in shares) at Sep. 30, 2021						189,627	52,916			11,468
Balance at end of period at Sep. 30, 2021	$ 905,517			$ 694,636		$ 19	$ 5	$ 1,665,805		$ (112,796)		$ (858,397)	$ 210,881

Consolidated Statements of Cash

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)	$ 367,571	$ (1,910,995)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, depletion and amortization	134,268	238,273
Amortization of intangible assets	9,346	10,879
Exploration expense, non-cash	0	561,629
Impairment of oil and natural gas properties	0	1,381,258
Asset retirement obligations accretion	4,065	4,403
Amortization of deferred financing costs	3,149	2,710
Unrealized loss on derivatives, net	277	2,208
Deferred taxes	0	(77,834)
Stock based compensation	9,143	8,871
Other	(85)	(2,059)
Changes in operating assets and liabilities:
Accounts receivable	(48,541)	44,532
Accounts payable	44,834	(15,953)
Accrued liabilities	(1,501)	(15,468)
Drilling advances	3,743	(174)
Other assets and liabilities, net	1,666	(1,281)
Net cash provided by operating activities	527,935	230,999
CASH FLOWS FROM INVESTING ACTIVITIES
Acquisitions	(10,817)	(73,702)
Additions to oil and natural gas properties	(162,744)	(157,325)
Changes in working capital associated with additions to oil and natural gas properties	12,435	(18,972)
Other investing	(2,316)	(842)
Net cash used in investing activities	(163,442)	(250,841)
CASH FLOW FROM FINANCING ACTIVITIES
Non-compete settlement	(42,074)	0
Dividends paid	(14,103)	0
Cash paid for debt modification	(4,976)	0
Distributions to noncontrolling interest owners	(5,706)	(594)
Other financing activities	(3,185)	(702)
Net cash used in financing activities	(312,031)	(14,258)
NET CHANGE IN CASH AND CASH EQUIVALENTS	52,462	(34,100)
Cash and cash equivalents – Beginning of period	192,561	182,633
Cash and cash equivalents – End of period	245,023	148,533
Supplemental cash items:
Cash paid (received) for income taxes	(1,128)	(724)
Cash paid for interest	26,483	25,445
Supplemental non-cash investing and financing activity:
Accruals or liabilities for capital expenditures	28,802	21,750
Supplemental non-cash lease operating activity:
Right-of-use assets obtained in exchange for operating lease obligations	4,429	5,500
Class A Common Stock
CASH FLOW FROM FINANCING ACTIVITIES
Common Stock repurchases	(70,316)	(12,962)
Class B Common Stock
CASH FLOW FROM FINANCING ACTIVITIES
Common Stock repurchases	$ (171,671)	$ 0

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Stockholders’ Equity (Unaudited) (Parenthetical) - $ / shares	Aug. 02, 2021	Sep. 30, 2021
Statement of Stockholders' Equity [Abstract]
Common stock, dividends, declared (in dollars per share)	$ 0.08	$ 0.08

Description of Business and Bas

Description of Business and Basis of Presentation	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Basis of Presentation	Description of Business and Basis of Presentation Organization and Nature of Operations Magnolia Oil & Gas Corporation (the “Company” or “Magnolia”) is an independent oil and natural gas company engaged in the acquisition, development, exploration, and production of oil, natural gas, and natural gas liquid (“NGL”) reserves. The Company’s oil and natural gas properties are located primarily in Karnes County and the Giddings area in South Texas where the Company targets the Eagle Ford Shale and Austin Chalk formations. Magnolia’s objective is to generate stock market value over the long-term through consistent organic production growth, high full cycle operating margins, an efficient capital program with short economic paybacks, significant free cash flow after capital expenditures, and effective reinvestment of free cash flow. Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) and the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial reporting. Accordingly, certain disclosures normally included in an Annual Report on Form 10-K have been omitted. The consolidated financial statements and related notes included in this Quarterly Report should be read in conjunction with the Company’s consolidated and combined financial statements and related notes included in the Company’s Annual Report on Form 10-K for the period ended December 31, 2020 (the “2020 Form 10-K”). Except as disclosed herein, there have been no material changes to the information disclosed in the notes to the consolidated and combined financial statements included in the Company’s 2020 Form 10-K. In the opinion of management, all normal, recurring adjustments and accruals considered necessary to present fairly, in all material respects, the Company’s interim financial results have been included. Operating results for the periods presented are not necessarily indicative of expected results for the full year. Certain reclassifications of prior period financial statements have been made to conform to current reporting practices. The consolidated financial statements include the accounts of the Company and its subsidiaries after elimination of intercompany transactions and balances. The Company’s interests in oil and natural gas exploration and production ventures and partnerships are proportionately consolidated. The Company reflects a noncontrolling interest representing primarily the interest owned by the Magnolia LLC Unit Holders through their ownership of Magnolia LLC Units in the consolidated financial statements. The noncontrolling interest is presented as a component of equity. See Note 12—Stockholders’ Equity for further discussion of the noncontrolling interest.

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 As of September 30, 2021, the Company’s significant accounting policies are consistent with those discussed in Note 2 — Summary of Significant Accounting Policies of its consolidated and combined financial statements contained in the Company’s 2020 Form 10-K. Recent Accounting Pronouncements In December 2019, the Financial Accounting Standards Board issued Accounting Standards Update No. 2019-12, Income Taxes (Topic 740): “Simplifying the Accounting for Income Taxes,” which reduces the complexity of accounting for income taxes by removing certain exceptions to the general principles and also simplifying areas such as separate entity financial statements and interim recognition of enactment of tax laws or rate changes. This standard is effective for interim and annual periods beginning after December 15, 2020 and shall be applied on either a prospective basis, a retrospective basis for all periods presented, or a modified retrospective basis through a cumulative-effect adjustment to retained earnings depending on which aspects of the new standard are applicable to an entity. The Company adopted this standard on a prospective basis on January 1, 2021. The adoption of this guidance did not have any material impact on the Company’s financial position, cash flows, or results of operations.

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition Magnolia’s revenues include the sale of crude oil, natural gas, and NGLs. Oil, natural gas, and NGL sales are recognized as revenue when production is sold to a customer in fulfillment of performance obligations under the terms of agreed contracts. Performance obligations are primarily comprised of delivery of oil, natural gas, or NGLs at a delivery point, as negotiated and reflected within each contract. Each barrel of oil, million Btu of natural gas, gallon of NGLs, or other unit of measure is separately identifiable and represents a distinct performance obligation to which the transaction price is allocated. The Company’s oil production is primarily sold under market-sensitive contracts that are typically priced at a differential to the New York Mercantile Exchange (“NYMEX”) price or at purchaser-posted prices for the producing area. For oil contracts, the Company generally records sales based on the net amount received. For natural gas contracts, the Company generally records wet gas sales (which consists of natural gas and NGLs based on end products after processing) at the wellhead or inlet of the gas processing plant (i.e., the point of control transfer) as revenues net of gathering, transportation and processing expenses if the processor is the customer and there is no redelivery of commodities to the Company at the tailgate of the plant. Conversely, the Company generally records residual natural gas and NGL sales at the tailgate of the plant (i.e., the point of control transfer) on a gross basis along with the associated gathering, transportation and processing expenses if the processor is a service provider and there is redelivery of one or several commodities to the Company at the tailgate of the plant. The facts and circumstances of an arrangement are considered and judgment is often required in making this determination. For processing contracts that require noncash consideration in exchange for processing services, the Company recognizes revenue and an equal gathering, transportation and processing expense for commodities transferred to the service provider. Customers are invoiced once the Company’s performance obligations have been satisfied. Payment terms and conditions vary by contract type, although terms generally include a requirement of payment within 30 days. There are no judgments that significantly affect the amount or timing of revenue from contracts with customers. Additionally, the Company’s product sales contracts do not give rise to material contract assets or contract liabilities. The Company’s receivables consist mainly of trade receivables from commodity sales and joint interest billings due from owners on properties the Company operates. Receivables from contracts with customers totaled $114.8 million as of September 30, 2021 and $72.0 million as of December 31, 2020. The Company has concluded that disaggregating revenue by product type appropriately depicts how the nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factors and has reflected this disaggregation of revenue on the Company’s consolidated statements of operations for all periods presented. Performance obligations are satisfied at a point in time once control of the product has been transferred to the customer. The Company considers a variety of facts and circumstances in assessing the point of control transfer, including, but not limited to: whether the purchaser can direct the use of the hydrocarbons, the transfer of significant risks and rewards, the Company’s right to payment, and the transfer of legal title. The Company does not disclose the value of unsatisfied performance obligations for contracts as all contracts have either an original expected length of one year or less, or the entire future consideration is variable and allocated entirely to a wholly unsatisfied performance obligation.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Acquisitions	Acquisitions 2020 Acquisitions On February 21, 2020, the Company completed the acquisition of certain non-operated oil and natural gas assets located in Karnes and DeWitt Counties, Texas, for approximately $69.7 million in cash. The transaction was accounted for as an asset acquisition.

Derivative Instruments

Derivative Instruments	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments As of September 30, 2021, the Company had settled all of its natural gas costless collar derivative contracts. Prior to September 30, 2021, Magnolia utilized natural gas costless collars to reduce its exposure to price volatility for a portion of its natural gas production volumes. The Company’s policies do not permit the use of derivative instruments for speculative purposes. Under the Company’s costless collar contracts, each collar had an established floor price and ceiling price. When the settlement price was below the floor price, the counterparty was required to make a payment to the Company and when the settlement price was above the ceiling price, the Company was required to make a payment to the counterparty. The Company has elected not to designate any of its derivative instruments as hedging instruments. Accordingly, changes in the fair value of the Company’s derivative instruments were recorded immediately to earnings as “Loss on derivatives, net” on the Company’s consolidated statements of operations. The following table summarizes the effects of derivative instruments on the Company’s consolidated statements of operations during the three and nine months ended September 30, 2021 and 2020: Three Months Ended Nine Months Ended (In thousands) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 Derivative settlements, realized (loss) $ (2,666) $ — $ (2,833) $ — Unrealized gain (loss) on derivatives 2,043 (2,208) (277) (2,208) (Loss) on derivatives, net $ (623) $ (2,208) $ (3,110) $ (2,208) The Company had no outstanding derivative contracts in place as of September 30, 2021. See Note 6 — Fair Value Measurement for the fair value hierarchy of the Company’s derivative contracts.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Certain of the Company’s assets and liabilities are carried at fair value and measured either on a recurring or nonrecurring basis. The Company’s fair value measurements are based either on actual market data or assumptions that other market participants would use in pricing an asset or liability in an orderly transaction, using the valuation hierarchy prescribed by GAAP under Accounting Standards Codification (“ASC”) 820. The three levels of the fair value hierarchy under ASC 820 are as follows: Level 1 - Quoted prices (unadjusted) in active markets for identical investments at the measurement date are used. Level 2 - Pricing inputs are other than quoted prices included within Level 1 that are observable for the investment, either directly or indirectly. Level 2 pricing inputs include quoted prices for similar investments in active markets, quoted prices for identical or similar investments in markets that are not active, inputs other than quoted prices that are observable for the investment, and inputs that are derived principally from or corroborated by observable market data by correlation or other means. Level 3 - Pricing inputs are unobservable and include situations where there is little, if any, market activity for the investment. The inputs used in determination of fair value require significant judgment and estimation. Recurring Fair Value Measurements Debt Obligations The carrying value and fair value of the financial instrument that is not carried at fair value in the accompanying consolidated balance sheets at September 30, 2021 and December 31, 2020 is as follows: September 30, 2021 December 31, 2020 (In thousands) Carrying Value Fair Value Carrying Value Fair Value Long-term debt $ 387,537 $ 410,880 $ 391,115 $ 407,500 The fair value of the 2026 Senior Notes at September 30, 2021 and December 31, 2020 is based on unadjusted quoted prices in an active market, which is considered a Level 1 input in the fair value hierarchy. The Company has other financial instruments consisting primarily of receivables, payables, and other current assets and liabilities that approximate fair value due to the nature of the instruments and their relatively short maturities. Non-financial assets and liabilities initially measured at fair value include assets acquired and liabilities assumed in business combinations and asset retirement obligations. Derivative Instruments The Company had no outstanding derivative instruments as of September 30, 2021. The fair values of the Company’s outstanding natural gas costless collar derivative instruments prior to September 30, 2021 were measured using an industry-standard pricing model and were provided by a third party. The inputs used in the third-party pricing model included quoted forward prices for natural gas, the contracted volumes, volatility factors, and time to maturity, which are considered Level 2 inputs. The Company’s derivative instruments outstanding as of December 31, 2020 were recorded at fair value within “Other current assets” on the Company’s consolidated balance sheet. These fair values were recorded by netting asset and liability positions with the same counterparty and were subject to contractual terms that provided for net settlement. The following table presents the classification of the outstanding derivative instruments and the fair value hierarchy table for the Company’s derivative assets and liabilities as of December 31, 2020 that were required to be measured at fair value on a recurring basis: Fair Value Measurements Using (In thousands) Level 1 Level 2 Level 3 Total Fair Value Netting Carrying Amount December 31, 2020 Current assets: Natural gas derivative instruments $ — $ 1,375 $ — $ 1,375 $ (1,098) $ 277 Current liabilities: Natural gas derivative instruments $ — $ 1,098 $ — $ 1,098 $ (1,098) $ — See Note 5 — Derivative Instruments for additional information on the Company’s derivative contracts. Nonrecurring Fair Value Measurements The Company applies the provisions of the fair value measurement standard on a nonrecurring basis to its non-financial assets and liabilities, including oil and natural gas properties. These assets and liabilities are not measured at fair value on a recurring basis but are subject to fair value adjustments when facts and circumstances arise that indicate a need for remeasurement. During the first quarter of 2020, Magnolia recorded impairments of $1.9 billion related to proved and unproved properties as a result of a sharp decline in commodity prices. Proved property impairment of $1.4 billion is included in “Impairment of oil and natural gas properties” and unproved property impairment of $0.6 billion is included in “Exploration expense” on the Company’s consolidated statement of operations for the nine months ended September 30, 2020. Proved and unproved properties that were impaired had aggregate fair values of $0.8 billion and $0.3 billion, respectively. The fair values of these oil and natural gas properties were measured using the income approach based on inputs that are not observable in the market, and therefore, represent Level 3 inputs. The Company calculated the estimated fair values of its oil and natural gas properties using a discounted future cash flow model. Significant inputs associated with the calculation of discounted future net cash flows include estimates of future commodity prices based on NYMEX strip pricing adjusted for price differentials, estimates of proved oil and natural gas reserves and risk adjusted probable and possible reserves, estimates of future expected operating and capital costs, and a market participant based weighted average cost of capital of 10% for proved property impairments and 12% for unproved property impairments. No impairments were recorded for the three and nine months ended September 30, 2021.

Intangible Assets

Intangible Assets	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Intangible Assets Non-Compete Agreement On July 31, 2018 (the “Closing Date”), the Company and EnerVest, separate and apart from the Business Combination, entered into the Non-Compete, which prohibited EnerVest and certain of its affiliates from competing with the Company in the Eagle Ford Shale (the “Market Area”) until July 31, 2022 (“Prohibited Period End Date”). In January 2021, the Company amended the Non-Compete such that, rather than delivering an aggregate of 4.0 million shares of Class A Common Stock upon the two and one-half year and the four year anniversaries of the Closing Date, the Company would deliver (i) the cash value of approximately 2.0 million shares of Class A Common Stock and approximately 0.4 million shares of Class A Common Stock on the two and one-half year anniversary of the Closing Date and (ii) an aggregate of 1.6 million shares of Class A Common Stock on the four year anniversary of the Closing Date, in each case subject to the terms and conditions of the Non-Compete. On February 1, 2021, as consideration for compliance with the Non-Compete, the Company paid $17.2 million in cash and issued 0.4 million shares of Class A Common Stock. On June 30, 2021, the Company amended the Non-Compete Prohibited Period End Date to terminate on June 30, 2021 and paid $24.9 million in cash in lieu of delivering the remaining 1.6 million shares of Class A Common Stock (the “Second Non-Compete Amendment”). On the Closing Date of the initial Business Combination, the Company recorded an estimated cost of $44.4 million for the Non-Compete as intangible assets on the Company’s consolidated balance sheet. These intangible assets had a definite life and were subject to amortization utilizing the straight-line method over their economic life, previously estimated to be two and one-half to four years. The Second Non-Compete Amendment resulted in the Company accelerating the amortization of the remaining intangible assets. The Company includes the amortization in “Amortization of intangible assets” on the Company’s consolidated statements of operations. (In thousands) September 30, 2021 December 31, 2020 Non-compete intangible assets $ 44,400 $ 44,400 Accumulated amortization (44,400) (35,054) Intangible assets, net $ — $ 9,346 Weighted average amortization period (in years) 2.70 3.25

Other Current Liabilities

Other Current Liabilities	9 Months Ended
	Sep. 30, 2021
Other Liabilities Disclosure [Abstract]
Other Current Liabilities	Other Current Liabilities The following table provides detail of the Company’s other current liabilities for the periods presented: (In thousands) September 30, 2021 December 31, 2020 Accrued capital expenditures $ 28,802 $ 16,368 Other 54,423 49,955 Total Other current liabilities $ 83,225 $ 66,323

Long-term Debt

Long-term Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Long-term Debt	Long-term Debt The Company’s debt is comprised of the following: (In thousands) September 30, 2021 December 31, 2020 Revolving credit facility $ — $ — Senior Notes due 2026 400,000 400,000 Total long-term debt 400,000 400,000 Less: Unamortized deferred financing cost (12,463) (8,885) Long-term debt, net $ 387,537 $ 391,115 Credit Facility In connection with the consummation of the Business Combination, the RBL Facility was entered into by and among Magnolia Operating, as borrower, Magnolia Intermediate, as its holding company, the banks, financial institutions, and other lending institutions from time to time party thereto, as lenders, the other parties from time to time party thereto, and Citibank, N.A., as administrative agent, collateral agent, issuing bank, and swingline lender, providing for maximum commitments in an aggregate principal amount of $1.0 billion with a letter of credit facility with a $100.0 million sublimit. The borrowing base as of September 30, 2021 was $450.0 million, which was reaffirmed in the semi-annual redetermination on October 15, 2021. The RBL Facility is guaranteed by certain parent companies and subsidiaries of Magnolia LLC and is collateralized by certain of Magnolia Operating’s oil and natural gas properties. Borrowings under the RBL Facility bear interest, at Magnolia Operating’s option, at a rate per annum equal to either the LIBOR rate or the alternative base rate plus the applicable margin. Additionally, Magnolia Operating is required to pay a commitment fee quarterly in arrears in respect of unused commitments under the RBL Facility. The applicable margin and the commitment fee rate are calculated based upon the utilization levels of the RBL Facility as a percentage of the borrowing base then in effect. The RBL Facility contains certain affirmative and negative covenants customary for financings of this type, including compliance with a leverage ratio of less than 4.00 to 1.00 and, if the leverage ratio is in excess of 3.00 to 1.00, a current ratio of greater than 1.00 to 1.00. As of September 30, 2021, the Company was in compliance with all covenants under the RBL Facility. Deferred financing costs incurred in connection with securing the RBL Facility were $11.7 million, which are amortized on a straight-line basis over a period of five years and included in “Interest expense, net” in the Company’s consolidated statements of operations. The Company recognized interest expense related to the RBL Facility of $1.0 million for each of the three months ended September 30, 2021 and 2020, and $3.1 million and $3.2 million for the nine months ended September 30, 2021 and 2020, respectively. The unamortized portion of the deferred financing costs is included in “Deferred financing costs, net” on the accompanying consolidated balance sheet as of September 30, 2021. The Company did not have any outstanding borrowings under its RBL Facility as of September 30, 2021. 2026 Senior Notes On July 31, 2018, the Issuers issued and sold $400.0 million aggregate principal amount of 2026 Senior Notes in a private placement under Rule 144A and Regulation S under the Securities Act of 1933, as amended. The 2026 Senior Notes were issued under the Indenture, dated as of July 31, 2018 (the “Indenture”), by and among the Issuers and Deutsche Bank Trust Company Americas, as trustee. The 2026 Senior Notes are guaranteed on a senior unsecured basis by the Company, Magnolia Operating, and Magnolia Intermediate and may be guaranteed by certain future subsidiaries of the Company. The 2026 Senior Notes will mature on August 1, 2026 and bear interest at the rate of 6.0% per annum. On April 5, 2021, the terms of the Indenture were amended to modify, among other things, the criteria used by the Company to make Restricted Payments (as defined in the Indenture). The amendment to the Indenture was accounted for as a debt modification. Costs incurred with third parties directly related to the modification were expensed as incurred. The Company incurred approximately $1.1 million of transaction fees related to the modification which were expensed and are reflected in “Interest expense, net” on the Company’s consolidated statements of operations for the nine months ended September 30, 2021. The Company also paid $5.0 million in fees to holders of the 2026 Senior Notes, which fees are recorded as deferred financing costs and amortized using the new effective interest rate applied prospectively over the remaining term of the 2026 Senior Notes. As of September 30, 2021, the Company had incurred and capitalized a total of $16.8 million of deferred financing costs related to the issuance of, and the amendment to the Indenture governing, the 2026 Senior Notes. These costs are amortized using the effective interest method over the term of the 2026 Senior Notes and are included in “Interest expense, net” in the Company’s consolidated statements of operations. The unamortized portion of the deferred financing costs is included as a reduction to the carrying value of the 2026 Senior Notes, which has been recorded as “Long-term debt, net” on the Company’s consolidated balance sheet as of September 30, 2021. The Company recognized interest expense related to the 2026 Senior Notes of $6.5 million and $6.3 million for the three months ended September 30, 2021 and 2020, respectively, and $20.5 million and $19.0 million for the nine months ended September 30, 2021 and 2020, respectively.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Matters From time to time, the Company is or may become involved in litigation in the ordinary course of business. Certain of the Magnolia LLC Unit Holders and EnerVest Energy Institutional Fund XIV-C, L.P. (collectively the “Co-Defendants”) and the Company have been named as defendants in a lawsuit where the plaintiffs claim to be entitled to a minority working interest in certain Karnes County Assets. The litigation is in the pre-trial stage. The exposure related to this litigation is currently not reasonably estimable. The Co-Defendants retained all such liability in connection with the Business Combination. A mineral owner in a Magnolia operated well in Karnes County, Texas filed a complaint with the Texas Railroad Commission (the “Commission”) challenging the validity of the permit to drill such well by questioning the long-standing process by which the Commission granted the permit. After the Commission affirmed the granting of the permit, and after judicial review of the Commission’s order by the 53rd Judicial District Court Travis County, Texas (the “District Court”), the District Court reversed and remanded the Commission’s order. The Commission and Magnolia have appealed the District Court’s judgment to the Third Court of Appeals in Austin, Texas, and the appeal is in the preliminary stage. At September 30, 2021, the Company does not believe the outcome of any such disputes or legal actions will have a material effect on its consolidated statements of operations, balance sheet, or cash flows. No amounts were accrued with respect to outstanding litigation at September 30, 2021 or September 30, 2020. Environmental Matters The Company, as an owner or lessee and operator of oil and natural gas properties, is subject to various federal, state, and local laws and regulations relating to discharge of materials into, and the protection of, the environment. These laws and regulations may, among other things, impose liability on a lessee under an oil and natural gas lease for the cost of pollution clean-up resulting from operations and subject the lessee to liability for pollution damages. In some instances, the Company may be directed to suspend or cease operations in an affected area. The Company maintains insurance coverage, which it believes is customary in the industry, although the Company is not fully insured against all environmental risks. Risks and Uncertainties The Company’s revenue, profitability, and future growth are substantially dependent upon the prevailing and future prices for oil and natural gas, which depend on numerous factors beyond the Company’s control such as overall oil and natural gas production and inventories in relevant markets, economic conditions, the global political environment, regulatory developments, and competition from other energy sources. Oil and natural gas prices historically have been volatile and may be subject to significant fluctuations in the future. The coronavirus disease 2019 (“COVID-19”) pandemic and related economic repercussions have created significant volatility, uncertainty, and turmoil in the oil and natural gas industry. While oil and natural gas prices have increased in 2021, demand and pricing may again decline if there is a resurgence of the outbreak across the U.S. or other locations across the world or as a result of any related social distancing guidelines, travel restrictions, and stay-at-home orders. The extent of any further impact of the pandemic, including the emergence and spread of variant strains of COVID-19, on the Company’s industry and business cannot be reasonably predicted at this time.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s income tax provision consists of the following components: Three Months Ended Nine Months Ended (In thousands) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 Current: Federal $ 2,604 $ — $ 4,248 $ (1,167) State 1,027 (339) 2,180 (339) 3,631 (339) 6,428 (1,506) Deferred: Federal — — — (71,792) State — — — (6,042) — — — (77,834) Income tax expense (benefit) $ 3,631 $ (339) $ 6,428 $ (79,340) The Company is subject to U.S. federal income tax, margin tax in the state of Texas, and Louisiana corporate income tax. The Company estimates its annual effective tax rate in recording its quarterly provision for income taxes in the various jurisdictions in which it operates. The Company’s effective tax rate for the three months ended September 30, 2021 and 2020 was 2.2% and negative 2.5%, respectively. The Company’s effective tax rate for the nine months ended September 30, 2021 and 2020 was 1.7% and 4.0%, respectively. As a result of impairments in the first quarter of 2020, the Company established full valuation allowances on the federal and state deferred tax assets, which resulted in additional differences between the effective tax rate and the statutory rate as of September 30, 2021 and September 30, 2020. The primary differences between the annual effective tax rate and the statutory rate of 21.0% are income attributable to noncontrolling interest, state taxes, and valuation allowances. As of September 30, 2021, the Company did not have an accrued liability for uncertain tax positions and does not anticipate recognition of any significant liabilities for uncertain tax positions during the next 12 months. For the quarter ended September 30, 2021, no amounts were incurred for income tax uncertainties or interest and penalties. Currently, the Company is not aware of any issues under review that could result in significant payments, accruals, or a material deviation from its position. The Company’s tax years since its formation remain subject to possible income tax examinations by its major taxing authorities for all periods. During the nine months ended September 30, 2021, the Magnolia LLC Unit Holders redeemed 19.9 million Magnolia LLC Units (and a corresponding number of shares of Class B Common Stock) for an equivalent number of shares of Class A Common Stock and subsequently sold these shares to the public. Magnolia did not receive any proceeds from the sale of shares of Class A Common Stock by the Magnolia LLC Unit Holders. The redemption and exchange of these Magnolia LLC Units created additional tax basis in Magnolia LLC. There was no net tax impact as the Company recorded a full valuation allowance. On March 27, 2020, the United States enacted the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”). Applying the net operating loss carryback provision resulted in an income tax benefit of $1.2 million in the first quarter of 2020.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity Class A Common Stock At September 30, 2021, there were 189.6 million shares of Class A Common Stock issued and 178.2 million shares of Class A Common Stock outstanding. The holders of Class A Common Stock and Class B Common Stock vote together as a single class on all matters and are entitled one vote for each share held. There is no cumulative voting with respect to the election of directors, which results in the holders of more than 50% of the Company’s outstanding common shares being able to elect all of the directors, subject to voting obligations under the Stockholder Agreement. In the event of a liquidation, dissolution, or winding up of the Company, the holders of the Class A Common Stock are entitled to share ratably in all assets remaining available for distribution to them after payment of liabilities and after provision is made for each class of stock, if any, having preference over the common stock. The holders of the Class A Common Stock have no preemptive or other subscription rights, and there are no sinking fund provisions applicable to such shares. Class B Common Stock At September 30, 2021, there were 52.9 million shares of Class B Common Stock issued and outstanding. Holders of Class B Common Stock vote together as a single class with holders of Class A Common Stock on all matters properly submitted to a vote of the stockholders. The holders of Class B Common Stock generally have the right to exchange all or a portion of their shares of Class B Common Stock, together with an equal number of Magnolia LLC Units, for the same number of shares of Class A Common Stock or, at Magnolia LLC’s option, an equivalent amount of cash. Upon the future redemption or exchange of Magnolia LLC Units held by any holder of Class B Common Stock, a corresponding number of shares of Class B Common Stock held by such holder of Class B Common Stock will be canceled. In the event of a liquidation, dissolution, or winding up of Magnolia LLC, the holders of the Class B Common Stock, through their ownership of Magnolia LLC Units, are entitled to share ratably in all assets remaining available for distribution to them after payment of liabilities and after provision is made for each class of units of Magnolia LLC, if any, having preference over the common units. The holders of the Class B Common Stock have no preemptive or other subscription rights, and there are no sinking fund provisions applicable to such shares. Share Repurchase Program The Company’s board of directors has authorized a share repurchase program of up to 20.0 million shares of Class A Common Stock. The program does not require purchases to be made within a particular time frame. As of September 30, 2021, the Company had repurchased 11.5 million shares under the program at a cost of $112.8 million. Dividends and Distributions Distribution On August 2, 2021, Magnolia LLC declared a cash distribution of $0.08 per Magnolia LLC Unit totaling $19.0 million, of which $14.2 million was distributed to the Company and $4.8 million was distributed to the Magnolia LLC Unit Holders. The distribution to the Magnolia LLC Unit Holders was recorded as a reduction of noncontrolling interest on the Company’s consolidated balance sheet as of September 30, 2021. Cash Dividend On August 2, 2021, the Company’s board of directors declared a semi-annual interim cash dividend of $0.08 per share of Class A Common Stock totaling approximately $14.2 million. The dividend was paid on September 1, 2021 to shareholders of record as of the close of business on August 12, 2021. Dividends in excess of retained earnings are recorded as a reduction of additional paid-in capital. The $14.2 million dividend declared during the third quarter of 2021 was recorded as a reduction of additional paid-in capital on the Company’s consolidated balance sheet as of September 30, 2021. Noncontrolling Interest Noncontrolling interest in Magnolia’s consolidated subsidiaries includes amounts attributable to Magnolia LLC Units that were issued to the Magnolia LLC Unit Holders in connection with the Business Combination. The noncontrolling interest percentage is affected by various equity transactions such as issuances and repurchases of Class A Common Stock, the exchange of Class B Common Stock (and corresponding Magnolia LLC Units) for Class A Common Stock, or the cancellation of Class B Common Stock (and corresponding Magnolia LLC Units). During the nine months ended September 30, 2021 Magnolia LLC repurchased and subsequently canceled 13.0 million Magnolia LLC Units with an equal number of shares of corresponding Class B Common Stock for $171.7 million of cash consideration (the “Class B Common Stock Repurchases”). During the same period, the Magnolia LLC Unit Holders redeemed 19.9 million Magnolia LLC Units (and a corresponding number of shares of Class B Common Stock) for an equivalent number of shares of Class A Common Stock and subsequently sold these shares to the public. Magnolia did not receive any proceeds from the sale of shares of Class A Common Stock by the Magnolia LLC Unit Holders. Magnolia funded the Class B Common Stock Repurchases with cash on hand. As of September 30, 2021, Magnolia owned approximately 77.1% of the interest in Magnolia LLC and the noncontrolling interest was 22.9%. Subsequent to September 30, 2021, the Magnolia LLC Unit Holders redeemed an additional 3.6 million Magnolia LLC Units (and a corresponding number of shares of Class B Common Stock) for an equivalent number of shares of Class A Common Stock and subsequently sold these shares to the public. In the first quarter of 2019, Magnolia Operating formed Highlander Oil & Gas Holdings LLC (“Highlander”) as a joint venture whereby MGY Louisiana LLC, a wholly owned subsidiary of Magnolia Operating, holds approximately 84.7% of the units of Highlander, with the remaining 15.3% attributable to noncontrolling interest.

Stock Based Compensation

Stock Based Compensation	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Stock Based Compensation	Stock Based Compensation On October 8, 2018, the Company’s board of directors adopted the “Magnolia Oil & Gas Corporation Long Term Incentive Plan” (the “Plan”), effective as of July 17, 2018. A total of 16.8 million shares of Class A Common Stock have been authorized for issuance under the Plan as of September 30, 2021. The Company grants stock based compensation awards in the form of restricted stock units (“RSU”), performance stock units (“PSU”), and performance restricted stock units (“PRSU”) to eligible employees and directors to enhance the Company and its affiliates’ ability to attract, retain, and motivate persons who make important contributions to the Company and its affiliates by providing these individuals with equity ownership opportunities. Shares issued as a result of awards granted under the Plan are generally new shares of Class A Common Stock. Stock based compensation expense is recognized net of forfeitures within “General and administrative expenses” and “Lease operating expenses” on the consolidated statements of operations and was $2.9 million for each of the three months ended September 30, 2021 and 2020, and $9.1 million and $8.9 million for the nine months ended September 30, 2021 and 2020, respectively. The Company has elected to account for forfeitures of awards granted under the Plan as they occur in determining compensation expense. The following table presents a summary of Magnolia’s unvested RSU, PSU, and PRSU activity for the three months ended September 30, 2021. Restricted Stock Units Performance Stock Units Performance Restricted Stock Units Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Unvested at June 30, 2021 1,552,716 $ 9.00 749,611 $ 11.06 1,010,491 $ 9.36 Granted 24,913 14.82 — — — — Vested (81,954) 13.65 (260,834) 14.58 — — Forfeited (26,461) 8.23 (28,363) 8.80 (37,854) 9.33 Unvested at September 30, 2021 1,469,214 $ 8.85 460,414 $ 9.20 972,637 $ 9.36 The following table presents a summary of Magnolia’s unvested RSU, PSU, and PRSU activity for the nine months ended September 30, 2021. Restricted Stock Units Performance Stock Units Performance Restricted Stock Units Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Unvested at December 31, 2020 1,686,637 $ 8.51 841,425 $ 10.95 — $ — Granted 480,041 10.62 — — 1,012,330 9.36 Vested (605,994) 9.20 (277,500) 14.58 — — Forfeited (91,470) 9.46 (103,511) 9.04 (39,693) 9.33 Unvested at September 30, 2021 1,469,214 $ 8.85 460,414 $ 9.20 972,637 $ 9.36 Restricted Stock Units The Company grants service-based RSU awards to employees and non-employee directors, which generally vest ratably over a three-year service period, in the case of awards to employees, and vest in full after one year, in the case of awards to directors. RSUs represent the right to receive shares of Class A Common Stock at the end of the vesting period equal to the number of RSUs that vest. RSUs are subject to restrictions on transfer and are generally subject to a risk of forfeiture if the award recipient ceases to be an employee or director of the Company prior to vesting of the award. Compensation expense for the service-based RSU awards is based upon the grant date market value of the award and such costs are recorded on a straight-line basis over the requisite service period for each separately vesting portion of the award, as if the award was, in-substance, multiple awards. Unrecognized compensation expense related to unvested RSUs as of September 30, 2021 was $7.9 million, which the Company expects to recognize over a weighted average period of 1.9 years. Performance Stock Units and Performance Restricted Stock Units The Company grants PRSUs to certain employees. Each PRSU represents the contingent right to receive one share of Class A Common Stock once the PRSU is both vested and earned. PRSUs generally vest either ratably over a three-year service period or at the end of a three-year service period, in each case, subject to the recipient’s continued employment or service through each applicable vesting date. Each PRSU is earned based on whether Magnolia’s stock price achieves a target average stock price for any 20 consecutive trading days during the five-year performance period. If PRSUs are not earned by the end of the five-year performance period (“Performance Condition”), the PRSUs will be forfeited and no shares of Class A Common Stock will be issued, even if the vesting conditions have been met. Compensation expense for the PRSU awards is based upon grant date fair market value of the award, calculated using a Monte Carlo simulation, as presented below, and such costs are recorded on a straight-line basis over the requisite service period for each separately vesting portion of the award, as if the award was, in-substance, multiple awards, as applicable. Unrecognized compensation expense related to unvested PRSUs as of September 30, 2021 was $7.3 million, which the Company expects to recognize over a weighted average period of 2.5 years. The Company grants PSUs to certain employees. Each PSU, to the extent earned, represents the contingent right to receive one share of Class A Common Stock and the awardee may earn between zero and 150% of the target number of PSUs granted based on the total shareholder return (“TSR”) of the Class A Common Stock relative to the TSR achieved by a specific industry peer group over a three-year performance period, the last day of which is also the vesting date. In addition to the TSR conditions, vesting of the PSUs is subject to the awardee’s continued employment through the date of settlement of the PSUs, which will occur within 60 days following the end of the performance period. Unrecognized compensation expense related to unvested PSUs as of September 30, 2021 was $1.0 million, which the Company expects to recognize over a weighted average period of 1.1 years. The grant date fair values of the PRSUs granted during the nine months ended September 30, 2021 and the PSUs granted during the nine months ended September 30, 2020, were $9.5 million and $2.5 million, respectively. Since the Performance Condition was met on March 17, 2021, the fair value of the PRSUs granted after this date was based upon the grant date market value of the award. The fair values of the awards granted prior to March 17, 2021 were determined using a Monte Carlo simulation. The following table summarizes the Monte Carlo simulation assumptions used to calculate the grant date fair value of the PRSUs in 2021 and the PSUs in 2020. Nine Months Ended PRSU and PSU Grant Date Fair Value Assumptions September 30, 2021 September 30, 2020 Expected term (in years) 3.64 2.85 Expected volatility 55.18% 33.50% Risk-free interest rate 0.56% 1.16%

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 ShareThe Company’s unvested share-based payment awards that contain nonforfeitable rights to dividends or dividend equivalents (whether paid or unpaid) are deemed participating securities and, therefore, have been deducted from earnings in computing basic and diluted net income (loss) per share under the two-class method. Diluted net income (loss) per share attributable to common stockholders is calculated under both the two-class method and the treasury stock method and the more dilutive of the two calculations is presented. The components of basic and diluted net income (loss) per share attributable to common stockholders are as follows: Three Months Ended Nine Months Ended (In thousands, except per share data) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 Basic: Net income (loss) attributable to Class A Common Stock $ 119,364 $ 9,147 $ 267,053 $ (1,236,135) Less: Dividends and net income allocated to participating securities 939 — 1,714 — Net income (loss), net of participating securities $ 118,425 $ 9,147 $ 265,339 $ (1,236,135) Weighted average number of common shares outstanding during the period - basic 174,764 166,467 172,281 166,728 Net income (loss) per share of Class A Common Stock - basic $ 0.68 $ 0.05 $ 1.54 $ (7.41) Diluted: Net income (loss) attributable to Class A Common Stock $ 119,364 $ 9,147 $ 267,053 $ (1,236,135) Less: Dividends and net income allocated to participating securities 934 — 1,705 — Net income (loss), net of participating securities $ 118,430 $ 9,147 $ 265,348 $ (1,236,135) Weighted average number of common shares outstanding during the period - basic 174,764 166,467 172,281 166,728 Add: Dilutive effect of stock based compensation and other 919 4,209 999 — Weighted average number of common shares outstanding during the period - diluted 175,683 170,676 173,280 166,728 Net income (loss) per share of Class A Common Stock - diluted $ 0.67 $ 0.05 $ 1.53 $ (7.41) For the three and nine months ended September 30, 2021, the Company excluded 60.4 million and 68.8 million, respectively, of weighted average shares of Class A Common Stock issuable upon the exchange of Class B Common Stock (and corresponding Magnolia LLC Units) as the effect was anti-dilutive. For the three and nine months ended September 30, 2020, the Company excluded 85.8 million weighted average shares of Class A Common Stock issuable upon the exchange of Class B Common Stock (and corresponding Magnolia LLC Units). In addition, for the nine months ended September 30, 2020, the Company excluded 4.0 million contingent shares of Class A Common Stock issuable to an affiliate of EnerVest, provided EnerVest did not compete in the Market Area, and 0.2 million RSUs and PSUs, because the effect was anti-dilutive.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions As of September 30, 2021, EnerVest Energy Institutional Fund XIV-A, L.P., a Delaware limited partnership, which is part of the Magnolia LLC Unit Holders, held more than 10% of the Company’s common stock and qualified as a principal owner of the Company, as defined in ASC 850, “Related Party Disclosures.” Distributions On August 2, 2021, Magnolia LLC declared a cash distribution of $0.08 per Magnolia LLC Unit totaling $19.0 million, of which $3.2 million was distributed to EnerVest Energy Institutional Fund XIV-A, L.P. Class B Common Stock Repurchases and Redemptions During the nine months ended September 30, 2021, EnerVest Energy Institutional Fund XIV-A, L.P. received $113.6 million in cash and surrendered 8.6 million Magnolia LLC Units with an equal number of shares of corresponding Class B Common Stock. EnerVest Energy Institutional Fund XIV-A, L.P. also redeemed 13.2 million Magnolia LLC Units (and a corresponding number of shares of Class B Common Stock) for an equivalent number of shares of Class A Common Stock, which were subsequently sold to the public. Subsequently, Magnolia LLC canceled the surrendered Magnolia LLC Units and a corresponding number of shares of Class B Common Stock. Magnolia did not receive any proceeds from the sale of shares of Class A Common Stock by EnerVest Energy Institutional Fund XIV-A, L.P.

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 consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) and the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial reporting. Accordingly, certain disclosures normally included in an Annual Report on Form 10-K have been omitted. The consolidated financial statements and related notes included in this Quarterly Report should be read in conjunction with the Company’s consolidated and combined financial statements and related notes included in the Company’s Annual Report on Form 10-K for the period ended December 31, 2020 (the “2020 Form 10-K”). Except as disclosed herein, there have been no material changes to the information disclosed in the notes to the consolidated and combined financial statements included in the Company’s 2020 Form 10-K. In the opinion of management, all normal, recurring adjustments and accruals considered necessary to present fairly, in all material respects, the Company’s interim financial results have been included. Operating results for the periods presented are not necessarily indicative of expected results for the full year.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In December 2019, the Financial Accounting Standards Board issued Accounting Standards Update No. 2019-12, Income Taxes (Topic 740): “Simplifying the Accounting for Income Taxes,” which reduces the complexity of accounting for income taxes by removing certain exceptions to the general principles and also simplifying areas such as separate entity financial statements and interim recognition of enactment of tax laws or rate changes. This standard is effective for interim and annual periods beginning after December 15, 2020 and shall be applied on either a prospective basis, a retrospective basis for all periods presented, or a modified retrospective basis through a cumulative-effect adjustment to retained earnings depending on which aspects of the new standard are applicable to an entity. The Company adopted this standard on a prospective basis on January 1, 2021. The adoption of this guidance did not have any material impact on the Company’s financial position, cash flows, or results of operations.

Derivative Instruments (Tables)

Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Effect of Derivative Instruments on Consolidated Statements of Operations	The following table summarizes the effects of derivative instruments on the Company’s consolidated statements of operations during the three and nine months ended September 30, 2021 and 2020: Three Months Ended Nine Months Ended (In thousands) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 Derivative settlements, realized (loss) $ (2,666) $ — $ (2,833) $ — Unrealized gain (loss) on derivatives 2,043 (2,208) (277) (2,208) (Loss) on derivatives, net $ (623) $ (2,208) $ (3,110) $ (2,208)

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Carrying Values and Fair Values of Financial Instruments Not Carried at Fair Value	The carrying value and fair value of the financial instrument that is not carried at fair value in the accompanying consolidated balance sheets at September 30, 2021 and December 31, 2020 is as follows: September 30, 2021 December 31, 2020 (In thousands) Carrying Value Fair Value Carrying Value Fair Value Long-term debt $ 387,537 $ 410,880 $ 391,115 $ 407,500
Schedule of Classification of Outstanding Derivative Instruments and Fair Value Hierarchy	The following table presents the classification of the outstanding derivative instruments and the fair value hierarchy table for the Company’s derivative assets and liabilities as of December 31, 2020 that were required to be measured at fair value on a recurring basis: Fair Value Measurements Using (In thousands) Level 1 Level 2 Level 3 Total Fair Value Netting Carrying Amount December 31, 2020 Current assets: Natural gas derivative instruments $ — $ 1,375 $ — $ 1,375 $ (1,098) $ 277 Current liabilities: Natural gas derivative instruments $ — $ 1,098 $ — $ 1,098 $ (1,098) $ —

Intangible Assets (Tables)

Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets	(In thousands) September 30, 2021 December 31, 2020 Non-compete intangible assets $ 44,400 $ 44,400 Accumulated amortization (44,400) (35,054) Intangible assets, net $ — $ 9,346 Weighted average amortization period (in years) 2.70 3.25

Other Current Liabilities (Tabl

Other Current Liabilities (Tables)	9 Months Ended
	Sep. 30, 2021
Other Liabilities Disclosure [Abstract]
Other Current Liabilities	The following table provides detail of the Company’s other current liabilities for the periods presented: (In thousands) September 30, 2021 December 31, 2020 Accrued capital expenditures $ 28,802 $ 16,368 Other 54,423 49,955 Total Other current liabilities $ 83,225 $ 66,323

Long-term Debt (Tables)

Long-term Debt (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Components of Debt	The Company’s debt is comprised of the following: (In thousands) September 30, 2021 December 31, 2020 Revolving credit facility $ — $ — Senior Notes due 2026 400,000 400,000 Total long-term debt 400,000 400,000 Less: Unamortized deferred financing cost (12,463) (8,885) Long-term debt, net $ 387,537 $ 391,115

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Components of Income Tax Provision (Benefit)	The Company’s income tax provision consists of the following components: Three Months Ended Nine Months Ended (In thousands) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 Current: Federal $ 2,604 $ — $ 4,248 $ (1,167) State 1,027 (339) 2,180 (339) 3,631 (339) 6,428 (1,506) Deferred: Federal — — — (71,792) State — — — (6,042) — — — (77,834) Income tax expense (benefit) $ 3,631 $ (339) $ 6,428 $ (79,340)

Stock Based Compensation (Table

Stock Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Unvested RSU, PSU, and PRSU Activity	The following table presents a summary of Magnolia’s unvested RSU, PSU, and PRSU activity for the three months ended September 30, 2021. Restricted Stock Units Performance Stock Units Performance Restricted Stock Units Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Unvested at June 30, 2021 1,552,716 $ 9.00 749,611 $ 11.06 1,010,491 $ 9.36 Granted 24,913 14.82 — — — — Vested (81,954) 13.65 (260,834) 14.58 — — Forfeited (26,461) 8.23 (28,363) 8.80 (37,854) 9.33 Unvested at September 30, 2021 1,469,214 $ 8.85 460,414 $ 9.20 972,637 $ 9.36 The following table presents a summary of Magnolia’s unvested RSU, PSU, and PRSU activity for the nine months ended September 30, 2021. Restricted Stock Units Performance Stock Units Performance Restricted Stock Units Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Unvested at December 31, 2020 1,686,637 $ 8.51 841,425 $ 10.95 — $ — Granted 480,041 10.62 — — 1,012,330 9.36 Vested (605,994) 9.20 (277,500) 14.58 — — Forfeited (91,470) 9.46 (103,511) 9.04 (39,693) 9.33 Unvested at September 30, 2021 1,469,214 $ 8.85 460,414 $ 9.20 972,637 $ 9.36
Schedule of Assumptions Used to Calculate Grant Date Fair Value of PSUs and PRSUs	The following table summarizes the Monte Carlo simulation assumptions used to calculate the grant date fair value of the PRSUs in 2021 and the PSUs in 2020. Nine Months Ended PRSU and PSU Grant Date Fair Value Assumptions September 30, 2021 September 30, 2020 Expected term (in years) 3.64 2.85 Expected volatility 55.18% 33.50% Risk-free interest rate 0.56% 1.16%

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Reconciliation of Numerators and Denominators for Basic and Diluted Per Share Computation	The components of basic and diluted net income (loss) per share attributable to common stockholders are as follows: Three Months Ended Nine Months Ended (In thousands, except per share data) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 Basic: Net income (loss) attributable to Class A Common Stock $ 119,364 $ 9,147 $ 267,053 $ (1,236,135) Less: Dividends and net income allocated to participating securities 939 — 1,714 — Net income (loss), net of participating securities $ 118,425 $ 9,147 $ 265,339 $ (1,236,135) Weighted average number of common shares outstanding during the period - basic 174,764 166,467 172,281 166,728 Net income (loss) per share of Class A Common Stock - basic $ 0.68 $ 0.05 $ 1.54 $ (7.41) Diluted: Net income (loss) attributable to Class A Common Stock $ 119,364 $ 9,147 $ 267,053 $ (1,236,135) Less: Dividends and net income allocated to participating securities 934 — 1,705 — Net income (loss), net of participating securities $ 118,430 $ 9,147 $ 265,348 $ (1,236,135) Weighted average number of common shares outstanding during the period - basic 174,764 166,467 172,281 166,728 Add: Dilutive effect of stock based compensation and other 919 4,209 999 — Weighted average number of common shares outstanding during the period - diluted 175,683 170,676 173,280 166,728 Net income (loss) per share of Class A Common Stock - diluted $ 0.67 $ 0.05 $ 1.53 $ (7.41)

Revenue Recognition (Details)

Revenue Recognition (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
General required payment period	30 days
Receivables from contracts with customers	$ 114.8	$ 72

Acquisitions - Narrative (Detai

Acquisitions - Narrative (Details) $ in Millions	Feb. 21, 2020USD ($)
Karnes and DeWitt County Assets
Asset Acquisition [Line Items]
Cash payments to acquire certain oil and natural gas properties	$ 69.7

Derivative Instruments - Schedu

Derivative Instruments - Schedule of Effect of Derivative Instruments on Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative settlements, realized (loss)	$ (2,666)	$ 0	$ (2,833)	$ 0
Unrealized gain (loss) on derivatives	2,043	(2,208)	(277)	(2,208)
Loss on derivatives, net	$ (623)	$ (2,208)	$ (3,110)	$ (2,208)

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Values and Fair Values of Financial Instruments Not Carried at Fair Value (Details) - Level 1 - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	$ 387,537	$ 391,115
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	$ 410,880	$ 407,500

Fair Value Measurements - Class

Fair Value Measurements - Classification of Outstanding Derivative Instruments and Fair Value Hierarchy (Details) - Fair Value, Recurring $ in Thousands	Dec. 31, 2020USD ($)
Current assets:
Natural gas derivative instruments	$ 1,375
Natural gas derivative instruments, Netting	(1,098)
Natural gas derivative instruments, Carrying Amount	277
Current liabilities:
Natural gas derivative instruments	1,098
Natural gas derivative instruments, Netting	(1,098)
Natural gas derivative instruments, Carrying Amount	0
Level 1
Current assets:
Natural gas derivative instruments	0
Current liabilities:
Natural gas derivative instruments	0
Level 2
Current assets:
Natural gas derivative instruments	1,375
Current liabilities:
Natural gas derivative instruments	1,098
Level 3
Current assets:
Natural gas derivative instruments	0
Current liabilities:
Natural gas derivative instruments	$ 0

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details)	3 Months Ended			9 Months Ended
	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairments recorded related to proved and unproved oil and natural gas properties	$ 0		$ 1,900,000,000	$ 0
Proved property impairment	$ 0	$ 0		$ 0	$ 1,381,258,000
Unproved property impairment					$ 600,000,000
Weighted Average | Cost of Capital | Market Participant Based
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Market participant based weighted average cost of capital for proved property impairments			0.10
Market participant based weighted average cost of capital for unproved property impairments			0.12
Fair Value, Nonrecurring | Fair Value | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Proved properties impaired, fair values as of the most recent date of impairment			$ 800,000,000
Unproved properties impaired, fair values as of the most recent date of impairment			$ 300,000,000

Intangible Assets - Narrative (

Intangible Assets - Narrative (Details) - USD ($) $ in Thousands, shares in Millions	Jun. 30, 2021	Feb. 01, 2021	Jul. 31, 2018	Jan. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
EnerVest
Finite-Lived Intangible Assets [Line Items]
Cash paid upon compliance of non-compete agreement milestones, milestone 1		$ 17,200
Cash paid upon compliance of non-compete agreement milestones, milestone 2	$ 24,900
EnerVest | Class A Common Stock
Finite-Lived Intangible Assets [Line Items]
Number of shares authorized for issuance based on compliance of non-compete agreement milestones (in shares)			4
Cash value of equity interest authorized for issuance upon compliance of non-compete agreement milestones, milestone 1 (in shares)				2
Number of shares authorized for issuance based on compliance of non-compete agreement milestones, milestone 1 (in shares)				0.4
Number of shares authorized for issuance based on compliance of non-compete agreement milestones, milestone 2 (in shares)	1.6			1.6
Equity interests issued upon compliance of non-compete agreement milestones, milestone 1 (in shares)		0.4
Non-Compete
Finite-Lived Intangible Assets [Line Items]
Estimated cost of intangible assets			$ 44,400		$ 44,400	$ 44,400
Non-Compete | Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated economic life of intangible asset			2 years 6 months	2 years 6 months	2 years 6 months
Non-Compete | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated economic life of intangible asset			4 years	4 years	4 years

Intangible Assets - Schedule of

Intangible Assets - Schedule of Intangible Asset (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Jul. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	$ (44,400)	$ (35,054)
Intangible assets, net	$ 0	$ 9,346
Weighted average amortization period (in years)	2 years 8 months 12 days	3 years 3 months
Non-Compete
Finite-Lived Intangible Assets [Line Items]
Non-compete intangible assets	$ 44,400	$ 44,400	$ 44,400

Other Current Liabilities (Deta

Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Other Liabilities Disclosure [Abstract]
Accrued capital expenditures	$ 28,802	$ 16,368
Other	54,423	49,955
Total Other current liabilities	$ 83,225	$ 66,323

Long-term Debt - Components of

Long-term Debt - Components of Debt (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total long-term debt	$ 400,000,000	$ 400,000,000
Less: Unamortized deferred financing cost	(12,463,000)	(8,885,000)
Long-term debt, net	387,537,000	391,115,000
Line of Credit | Revolving credit facility
Debt Instrument [Line Items]
Total long-term debt	0	0
Senior Notes | Senior Notes due 2026
Debt Instrument [Line Items]
Total long-term debt	$ 400,000,000	$ 400,000,000

Long-term Debt - Credit Facilit

Long-term Debt - Credit Facility Narrative (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)
Line of Credit Facility [Line Items]
Outstanding borrowings	$ 400,000,000		$ 400,000,000		$ 400,000,000
Line of Credit | RBL Facility
Line of Credit Facility [Line Items]
Deferred financing costs incurred in connection with securing the RBL Facility	11,700,000		$ 11,700,000
Amortization period			5 years
Interest expense	1,000,000	$ 1,000,000	$ 3,100,000	$ 3,200,000
Outstanding borrowings	0		0		$ 0
Line of Credit | RBL Facility | Magnolia Operating
Line of Credit Facility [Line Items]
Maximum commitments, aggregate principal amount	1,000,000,000		1,000,000,000
Borrowing base	$ 450,000,000		$ 450,000,000
Leverage ratio (less than)	4		4
Leverage ratio, minimum threshold for current ratio	3		3
Current ratio (greater than)	1		1
Line of Credit | Letter of Credit Sublimit | Magnolia Operating
Line of Credit Facility [Line Items]
Maximum commitments, aggregate principal amount	$ 100,000,000		$ 100,000,000

Long-term Debt - 2026 Senior No

Long-term Debt - 2026 Senior Notes Narrative (Details) - Senior Notes - Senior Notes due 2026 - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Apr. 05, 2021	Jul. 31, 2018
Debt Instrument [Line Items]
Aggregate principal amount						$ 400,000,000
Stated interest rate						6.00%
Transaction fees			$ 1,100,000
Deferred financing costs incurred in connection with securing the 2026 Senior Notes	$ 16,800,000		16,800,000		$ 5,000,000
Interest expense	$ 6,500,000	$ 6,300,000	$ 20,500,000	$ 19,000,000
Redemption price, percentage of principal amount of Notes redeemed			100.00%

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($)	Sep. 30, 2021	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Amounts accrued with respect to outstanding litigation	$ 0	$ 0

Income Taxes - Components of In

Income Taxes - Components of Income Tax Provision (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Current:
Federal	$ 2,604	$ 0	$ 4,248	$ (1,167)
State	1,027	(339)	2,180	(339)
Current income tax provision	3,631	(339)	6,428	(1,506)
Deferred:
Federal	0	0	0	(71,792)
State	0	0	0	(6,042)
Deferred income tax provision	0	0	0	(77,834)
Income tax expense (benefit)	$ 3,631	$ (339)	$ 6,428	$ (79,340)

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) shares in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Valuation Allowance [Line Items]
Effective tax rate	2.20%	(2.50%)		1.70%	4.00%
Liabilities for uncertain tax positions	$ 0			$ 0
Amounts incurred for interest and penalties	0			0
Income tax benefit resulting from applying NOL carryback provision			$ 1,200,000
Net deferred tax asset	203,100,000			203,100,000
Valuation allowance	$ 203,100,000			$ 203,100,000
Class B Common Stock | Magnolia LLC Unit Holders
Valuation Allowance [Line Items]
Stock redeemed (in shares)				19.9
Magnolia LLC Units | Magnolia LLC Unit Holders
Valuation Allowance [Line Items]
Stock redeemed (in shares)				19.9

Stockholders' Equity (Details)

Stockholders' Equity (Details) $ / shares in Units, $ in Thousands	Aug. 02, 2021USD ($)$ / shares	Nov. 02, 2021shares	Sep. 30, 2021USD ($)votePerShare$ / sharesshares	Jun. 30, 2021USD ($)	Mar. 31, 2021USD ($)	Sep. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Jun. 30, 2019	Sep. 30, 2021USD ($)votePerShareshares	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)votePerShareshares	Dec. 31, 2020shares
Class of Stock [Line Items]
Dividends declared | $	$ 14,200		$ 14,233
Common stock, dividends, declared (in dollars per share) | $ / shares	$ 0.08		$ 0.08
Highlander
Class of Stock [Line Items]
Percentage of interest owned by noncontrolling interest holders								15.30%
VIE, Primary Beneficiary | Magnolia LLC
Class of Stock [Line Items]
Percentage of interest owned									77.10%
Percentage of interest owned by noncontrolling interest holders			22.90%						22.90%		22.90%
MGY Louisiana LLC | Highlander
Class of Stock [Line Items]
Percentage of units held								84.70%
Magnolia LLC
Class of Stock [Line Items]
Distribution made to LLC member, distributions declared (in dollars per share) | $ / shares	$ 0.08
Total declared distributions | $	$ 19,000
Stock repurchased, cash consideration | $									$ 171,700
Magnolia LLC Unit Holders
Class of Stock [Line Items]
Distribution made to LLC member, cash distributions declared | $	$ 4,800
Class A Common Stock
Class of Stock [Line Items]
Common stock, shares issued (in shares)			189,627,000						189,627,000		189,627,000	168,755,000
Common stock, shares outstanding (in shares)			178,160,000						178,160,000		178,160,000	163,280,000
Number of votes for each share held | votePerShare			1						1		1
Number of shares authorized to be repurchased (in shares)			20,000,000						20,000,000		20,000,000
Number of shares repurchased (in shares)											11,500,000
Total cost of shares repurchased | $			$ 29,510	$ 24,047	$ 20,281	$ 6,480	$ 6,483				$ 112,800
Stock repurchased, cash consideration | $									$ 70,316	$ 12,962
Class B Common Stock
Class of Stock [Line Items]
Common stock, shares issued (in shares)			52,916,000						52,916,000		52,916,000	85,790,000
Common stock, shares outstanding (in shares)			52,916,000						52,916,000		52,916,000	85,790,000
Number of votes for each share held | votePerShare			1						1		1
Stock repurchased, cash consideration | $									$ 171,671	$ 0
Class B Common Stock | Magnolia LLC
Class of Stock [Line Items]
Stock repurchased and subsequently canceled (in shares)									13,000,000
Class B Common Stock | Magnolia LLC Unit Holders
Class of Stock [Line Items]
Stock redeemed (in shares)									19,900,000
Class B Common Stock | Magnolia LLC Unit Holders | Subsequent Event
Class of Stock [Line Items]
Stock redeemed (in shares)		3,600,000
Magnolia LLC Units | Magnolia LLC
Class of Stock [Line Items]
Stock repurchased and subsequently canceled (in shares)									13,000,000
Magnolia LLC Units | Magnolia LLC Unit Holders
Class of Stock [Line Items]
Stock redeemed (in shares)									19,900,000
Magnolia LLC Units | Magnolia LLC Unit Holders | Subsequent Event
Class of Stock [Line Items]
Stock redeemed (in shares)		3,600,000

Stock Based Compensation - Narr

Stock Based Compensation - Narrative (Details) - USD ($) $ in Millions	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]
Stock based compensation expense	$ 2.9	$ 2.9	$ 9.1	$ 8.9
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	7.9		$ 7.9
Weighted average period over which unrecognized compensation expense is expected to be recognized			1 year 10 months 24 days
RSUs | Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
RSUs | Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 year
PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Unrecognized compensation expense	7.3		$ 7.3
Weighted average period over which unrecognized compensation expense is expected to be recognized			2 years 6 months
Number of consecutive trading days required to earn PRSUs			20 days
Performance period			5 years
Grant date fair value			$ 9.5
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 1		$ 1
Weighted average period over which unrecognized compensation expense is expected to be recognized			1 year 1 month 6 days
Performance period			3 years
Settlement date, period following performance period			60 days
Grant date fair value				$ 2.5
Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance (in shares)	16,800,000		16,800,000
Class A Common Stock | PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contingent right to receive common stock, number of shares receivable for each PSU (in shares)	1		1
Class A Common Stock | PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contingent right to receive common stock, number of shares receivable for each PSU (in shares)	1		1
Class A Common Stock | PSUs | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			0.00%
Class A Common Stock | PSUs | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			150.00%

Stock Based Compensation - Sche

Stock Based Compensation - Schedule of Unvested RSU, PSU, and PRSU Activity (Details) - $ / shares	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021
Restricted Stock Units
Units
Unvested stock units, beginning of period (in shares)	1,552,716	1,686,637
Granted (in shares)	24,913	480,041
Vested (in shares)	(81,954)	(605,994)
Forfeited (in shares)	(26,461)	(91,470)
Unvested stock units, end of period (in shares)	1,469,214	1,469,214
Weighted Average Grant Date Fair Value
Unvested stock units, beginning of period (in dollars per share)	$ 9	$ 8.51
Granted (in dollars per share)	14.82	10.62
Vested (in dollars per share)	13.65	9.20
Forfeited (in dollars per share)	8.23	9.46
Unvested stock units, end of period (in dollars per share)	$ 8.85	$ 8.85
Performance Stock Units
Units
Unvested stock units, beginning of period (in shares)	749,611	841,425
Granted (in shares)	0	0
Vested (in shares)	(260,834)	(277,500)
Forfeited (in shares)	(28,363)	(103,511)
Unvested stock units, end of period (in shares)	460,414	460,414
Weighted Average Grant Date Fair Value
Unvested stock units, beginning of period (in dollars per share)	$ 11.06	$ 10.95
Granted (in dollars per share)	0	0
Vested (in dollars per share)	14.58	14.58
Forfeited (in dollars per share)	8.80	9.04
Unvested stock units, end of period (in dollars per share)	$ 9.20	$ 9.20
Performance Restricted Stock Units
Units
Unvested stock units, beginning of period (in shares)	1,010,491	0
Granted (in shares)	0	1,012,330
Vested (in shares)	0	0
Forfeited (in shares)	(37,854)	(39,693)
Unvested stock units, end of period (in shares)	972,637	972,637
Weighted Average Grant Date Fair Value
Unvested stock units, beginning of period (in dollars per share)	$ 9.36	$ 0
Granted (in dollars per share)	0	9.36
Vested (in dollars per share)	0	0
Forfeited (in dollars per share)	9.33	9.33
Unvested stock units, end of period (in dollars per share)	$ 9.36	$ 9.36

Stock Based Compensation - Sc_2

Stock Based Compensation - Schedule of Assumptions Used to Calculate Grant Date Fair Value of PSUs and PRSUs (Details)	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	3 years 7 months 20 days
Expected volatility	55.18%
Risk-free interest rate	0.56%
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		2 years 10 months 6 days
Expected volatility		33.50%
Risk-free interest rate		1.16%

Earnings (Loss) Per Share - Rec

Earnings (Loss) Per Share - Reconciliation of Numerators and Denominators for Basic and Diluted Per Share Computation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Basic:
Net income (loss) attributable to Class A Common Stock	$ 119,364	$ 9,147	$ 267,053	$ (1,236,135)
Less: Dividends and net income allocated to participating securities	939	0	1,714	0
Net income (loss), net of participating securities	$ 118,425	$ 9,147	$ 265,339	$ (1,236,135)
Weighted average number of common shares outstanding during the period - basic (in shares)	174,764	166,467	172,281	166,728
Diluted:
Net income (loss) attributable to Class A Common Stock	$ 119,364	$ 9,147	$ 267,053	$ (1,236,135)
Less: Dividends and net income allocated to participating securities	934	0	1,705	0
Net income (loss), net of participating securities	$ 118,430	$ 9,147	$ 265,348	$ (1,236,135)
Weighted average number of common shares outstanding during the period - basic (in shares)	174,764	166,467	172,281	166,728
Add: Dilutive effect of stock based compensation and other (in shares)	919	4,209	999	0
Weighted average number of common shares outstanding during the period - diluted (in shares)	175,683	170,676	173,280	166,728
Class A Common Stock
Basic:
Net income (loss) per share of Class A Common Stock - basic (in dollars per share)	$ 0.68	$ 0.05	$ 1.54	$ (7.41)
Diluted:
Net income (loss) per share of Class A Common Stock - diluted (in dollars per share)	$ 0.67	$ 0.05	$ 1.53	$ (7.41)

Earnings (Loss) Per Share - Nar

Earnings (Loss) Per Share - Narrative (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Class A Common Stock
Class of Stock [Line Items]
Shares excluded due to antidilutive effect (in shares)	60.4	85.8	68.8	85.8
Contingent Shares of Class A Common Stock Issuable to EnerVest
Class of Stock [Line Items]
Shares excluded due to antidilutive effect (in shares)				4
RSUs and PSUs
Class of Stock [Line Items]
Shares excluded due to antidilutive effect (in shares)				0.2

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	Aug. 02, 2021	Nov. 02, 2021	Sep. 30, 2021	Sep. 30, 2020
Class B Common Stock
Related Party Transaction [Line Items]
Stock repurchased, cash consideration			$ 171,671	$ 0
Magnolia LLC
Related Party Transaction [Line Items]
Distribution made to LLC member, distributions declared (in dollars per share)	$ 0.08
Total declared distributions	$ 19,000
Stock repurchased, cash consideration			$ 171,700
Magnolia LLC | Class B Common Stock
Related Party Transaction [Line Items]
Stock repurchased and subsequently canceled (in shares)			13
Magnolia LLC | Magnolia LLC Units
Related Party Transaction [Line Items]
Stock repurchased and subsequently canceled (in shares)			13
EnerVest Energy Institutional Fund XIV-A, L.P.
Related Party Transaction [Line Items]
Distribution made to limited partner	$ 3,200
EnerVest Energy Institutional Fund XIV-A, L.P. | Class B Common Stock | Subsequent Event
Related Party Transaction [Line Items]
Stock redeemed (in shares)		2.4
EnerVest Energy Institutional Fund XIV-A, L.P. | Magnolia LLC Units | Subsequent Event
Related Party Transaction [Line Items]
Stock redeemed (in shares)		2.4
Affiliate of EnerVest | EnerVest Energy Institutional Fund XIV-A, L.P. | Class B Common Stock
Related Party Transaction [Line Items]
Stock redeemed (in shares)			13.2
Affiliate of EnerVest | EnerVest Energy Institutional Fund XIV-A, L.P. | Magnolia LLC Units
Related Party Transaction [Line Items]
Stock redeemed (in shares)			13.2
EnerVest Energy Institutional Fund XIV-A, L.P. | Affiliate of EnerVest | Magnolia LLC
Related Party Transaction [Line Items]
Stock repurchased, cash consideration			$ 113,600
EnerVest Energy Institutional Fund XIV-A, L.P. | Affiliate of EnerVest | Magnolia LLC | Class B Common Stock
Related Party Transaction [Line Items]
Stock repurchased and subsequently canceled (in shares)			8.6
EnerVest Energy Institutional Fund XIV-A, L.P. | Affiliate of EnerVest | Magnolia LLC | Magnolia LLC Units
Related Party Transaction [Line Items]
Stock repurchased and subsequently canceled (in shares)			8.6