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Supplemental Oil and Gas Reserve Information - Unaudited - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2021 MBoe	Dec. 31, 2021 Boe	Dec. 31, 2021	Dec. 31, 2021 MMBoe	Dec. 31, 2021 $ / bbl	Dec. 31, 2021 $ / MMBTU	Dec. 31, 2020 MBoe	Dec. 31, 2020 Boe	Dec. 31, 2020	Dec. 31, 2020 MMBoe	Dec. 31, 2020 $ / bbl	Dec. 31, 2020 $ / MMBTU	Dec. 31, 2019 MBoe	Dec. 31, 2019 Boe	Dec. 31, 2019	Dec. 31, 2019 MMBoe	Dec. 31, 2019 $ / bbl	Dec. 31, 2019 $ / MMBTU
Reserve Quantities [Line Items]
Net positive (negative) revisions of previous estimates (MMBoe)	53,871,000	53,900,000					(86,251,000)	(86,300,000)					(63,349,000)	(63,300,000)
Percentage of net positive (negative) revisions			30.00%						(30.00%)						(20.00%)
Positive (negative) revisions of previous estimates - proved developed reserves (MMBoe)		20,300,000
Estimated extensions and discoveries of reserves associated with new wells (MMBoe)		2,600,000						3,200,000						10,300,000
Additions due to extensions and discoveries (MMBoe)	10,157,000	10,200,000					6,021,000	6,000,000.0					63,861,000	63,900,000
Additional proved undeveloped reserves (MMBoe)		7,600,000						2,800,000						53,600,000
Divested reserves associated with non-operated properties (MMBoe)	31,461,000							0					2,531,000
Purchases of reserves in place (MMBoe)	57,015,000															0
Unweighted arithmetic average first-day-of-the-month prices for oil (in dollars per Bbl) | $ / bbl					66.55						39.54						55.85
Unweighted arithmetic average first-day-of-the-month prices for natural gas (in dollars per MMBtu) | $ / MMBTU						3.64						2.03						2.62
Revision of Previous Estimate Due to Realized Prices
Reserve Quantities [Line Items]
Net positive (negative) revisions of previous estimates (MMBoe)		37,200,000								(29.3)						11.2
Positive (negative) revisions of previous estimates - proved developed reserves (MMBoe)		36,500,000								(31.9)				(9.6)
Positive (negative) revisions of previous estimates - proved undeveloped reserves (MMBoe) | MMBoe										2.6
Revision Due to Performance
Reserve Quantities [Line Items]
Net positive (negative) revisions of previous estimates (MMBoe)		22,900,000														(51.2)
Positive (negative) revisions of previous estimates - proved developed reserves (MMBoe)		(17,600,000)												(30.2)
Positive (negative) revisions of previous estimates - proved undeveloped reserves (MMBoe)		(5,100,000)												21.1
Revision of Previous Estimate Due to (Mis)Alignment With Development Plan
Reserve Quantities [Line Items]
Net positive (negative) revisions of previous estimates (MMBoe) | MMBoe										(60.1)						(7.6)
Positive (negative) revisions of previous estimates - proved undeveloped reserves (MMBoe)		38,600,000								(54.5)						(7.0)
Revision of Previous Estimate Due to Lower Operating Expenses
Reserve Quantities [Line Items]
Net positive (negative) revisions of previous estimates (MMBoe)		(6,200,000)								(1.5)						(6.7)
Positive (negative) revisions of previous estimates - proved developed reserves (MMBoe)		6,000,000.0												5.1
Positive (negative) revisions of previous estimates - proved undeveloped reserves (MMBoe)								(1.7)
Revision Due To Removal Of Midstream Operations
Reserve Quantities [Line Items]
Net positive (negative) revisions of previous estimates (MMBoe)		(5,200,000)
Positive (negative) revisions of previous estimates - proved developed reserves (MMBoe)		(4,600,000)
Revisions Due to Addition of Proved Undeveloped Reserves (PUDs)
Reserve Quantities [Line Items]
Net positive (negative) revisions of previous estimates (MMBoe) | MMBoe										(5.6)
Bakken or Three Forks Formations Area
Reserve Quantities [Line Items]
Percentage of reserves produced from wells in certain formations															60.00%
Percentage of proved undeveloped reserves															63.00%
Permian Basin
Reserve Quantities [Line Items]
Percentage of reserves produced from wells in certain formations									99.00%						40.00%
Percentage of proved undeveloped reserves															37.00%
Divested reserves associated with non-operated properties (MMBoe)		31,500,000												31,500,000
Williston Basin
Reserve Quantities [Line Items]
Percentage of reserves produced from wells in certain formations									1.00%
Divested reserves associated with non-operated properties (MMBoe)		2,500,000												2,500,000
Purchases of reserves in place (MMBoe) | MMBoe				57,000,000.0

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