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Oil and Gas Reserves Information (Unaudited) - Summary of Changes in Net Quantities of Crude Oil and Natural Gas Reserves (Detail)	5 Months Ended			7 Months Ended	12 Months Ended
	Dec. 31, 2018 MBbls	Dec. 31, 2018 MMcf MBbls	Dec. 31, 2018 MBbls MMBbls	Aug. 13, 2018 MBbls MMcf	Dec. 31, 2020 MMcf MMBbls Bcf	Dec. 31, 2019 MMcf MBbls MMBbls	Dec. 31, 2019 MMcf MMBbls	Dec. 31, 2019 MMcf MMBbls	Dec. 31, 2019 MMcf Bcf MMBbls	Dec. 31, 2018 MBbls	Dec. 31, 2018 MBbls MMcf	Dec. 31, 2018 MBbls Bcf	Dec. 31, 2018 MMcf	Dec. 31, 2018 MMBbls	Dec. 31, 2017 MBbls MMcf
Changes in Oil Prices
Proved Reserves:
Revisions of previous estimates | Bcf					2.9				0.5			0
Changes in Natural Gas Prices [Member]
Proved Reserves:
Revisions of previous estimates | Bcf					68.2				228.5			0
Oil (MBbls)
Proved Reserves:
Beginning of period	28,994				16,747	23,612		23,612
Revisions of previous estimates	5				(4,241)			(4,621)
Extensions and discoveries	0				2	259
Acquisitions of minerals in place	0				0	240
Sales of minerals in place	(4,002)				0			(58)
Production	(1,385)				(1,508)			(2,685)
End of period	23,612		23,612	28,994	11,000			16,747		23,612
Proved Developed Reserves:
Proved Developed Reserves	21,466	21,466	21,466	22,845	11,000	15,104	15,104	15,104	15,104	21,466	21,466	21,466		21,466
Proved Undeveloped Reserves:
Proved Undeveloped Reserves	2,146	2,146	2,146	6,149	0	1,643	1,643	1,643	1,643	2,146	2,146	2,146		2,146
Oil (MBbls) | Predecessor
Proved Reserves:
Beginning of period | MBbls	6,050			7,552						7,552
Revisions of previous estimates | MBbls				4
Extensions and discoveries | MBbls				5,651
Acquisitions of minerals in place | MBbls				0
Sales of minerals in place | MBbls				(6,870)
Production | MBbls				(287)
End of period | MBbls				6,050
Proved Developed Reserves:
Proved Developed Reserves | MBbls				403											7,552
Proved Undeveloped Reserves:
Proved Undeveloped Reserves | MBbls				5,647											0
Natural Gas (MMcf)
Proved Reserves:
Beginning of period		2,246,501			5,341,497		2,282,758
Revisions of previous estimates		23,949			306,552		62,697
Extensions and discoveries		30,126			365,663		315,286
Acquisitions of minerals in place		33,612			0		3,023,109
Sales of minerals in place		(6,399)			0		(49,520)
Production		(45,031)			(450,836)		(292,833)
End of period		2,282,758		2,246,501	5,562,876		5,341,497				2,282,758
Proved Developed Reserves:
Proved Developed Reserves				550,198	1,967,288	1,890,357	1,890,357	1,890,357	1,890,357				583,107
Proved Undeveloped Reserves:
Proved Undeveloped Reserves				1,696,303	3,595,588	3,451,140	3,451,140	3,451,140	3,451,140				1,699,651
Natural Gas (MMcf) | Predecessor
Proved Reserves:
Beginning of period		2,195,273		1,116,956							1,116,956
Revisions of previous estimates				17,778
Extensions and discoveries				950,032
Acquisitions of minerals in place | MBbls				220,088
Sales of minerals in place				(54,341)
Production				(55,240)
End of period				2,195,273
Proved Developed Reserves:
Proved Developed Reserves				500,031											436,114
Proved Undeveloped Reserves:
Proved Undeveloped Reserves				1,695,242											680,842

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Additions to proved reserves that result from (1) extension of the proved acreage of previously discovered (old) reservoirs through additional drilling in periods after discovery and (2) discovery of new fields with proved reserves or of new reservoirs of proved reserves in old fields.

+ References

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-Subsection Instruction 2

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The net quantity of proved reserves as of the balance sheet date. Proved oil reserves are the estimated quantities of crude oil and natural gas liquids which geological and engineering data demonstrate with reasonable certainty to be recoverable.

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Revisions represent changes in previous estimates of proved reserves, either upward or downward, resulting from new information (except for an increase in proved acreage) normally obtained from development drilling and production history or resulting from change in economic factors.

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Sales of minerals in place.

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