Cash flows relating to proved reserves abstract.

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- Definition

Future costs abstract.

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No definition available.

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- Definition

Percentage of discount factor.

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No definition available.

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- Definition

Amount of estimated future accumulated cash inflow from the sale of proved oil and gas reserves.

+ References

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- Definition

Amount of estimated future accumulated cash outflow for costs to be incurred in developing proved oil and gas reserves.

+ References

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- Definition

Amount of estimated future accumulated cash outflow for income tax, based on the future income less future expense derived from production and sale of proved oil and gas reserves.

+ References

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- Definition

Amount, after future accumulated cash outflow for development and production costs and future income tax, of estimated future accumulated cash inflow from the sale of proved oil and gas reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Form 20-F
-Section Item 18
-Subsection Instruction 2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62479-109447

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62455-109447

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- Definition

Amount of estimated future accumulated cash outflow for costs to be incurred in producing proved oil and gas reserves.

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- Definition

Amount of discount on future accumulated cash inflow, after deducting future accumulated cash outflow for development and production costs and future income tax, from sale of proved oil and gas reserves, using a discount rate of ten percent a year.

+ References

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- Definition

Amount of discounted future accumulated cash inflow relating to proved oil and gas reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Form 20-F
-Section Item 18
-Subsection Instruction 2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
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Oil and Gas Reserves Information (Unaudited) - Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Reserves (Detail) - USD ($) $ in Thousands	5 Months Ended	7 Months Ended	12 Months Ended
	Dec. 31, 2018	Aug. 13, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2017
Cash Flows Relating to Proved Reserves:
Future Cash Flows	$ 8,054,092		$ 9,871,616	$ 13,078,155
Future Costs:
Production	(2,160,912)		(3,173,350)	(3,562,042)
Development and Abandonment	(1,800,335)		(2,592,520)	(3,171,351)
Future Income Taxes	(622,241)		(154,872)	(676,759)
Future Net Cash Flows	$ 3,470,604		$ 3,950,874	$ 5,668,003
Percentage of discount factor	10.00%	10.00%	10.00%	10.00%
10% Discount Factor	$ (1,996,764)		$ (2,015,149)	$ (2,754,792)
Standardized Measure of Discounted Future Net Cash Flows	$ 1,473,840	$ 1,317,383	$ 1,935,725	$ 2,913,211
Predecessor
Cash Flows Relating to Proved Reserves:
Future Cash Flows		6,384,203
Future Costs:
Production		(1,804,559)
Development and Abandonment		(1,945,141)
Future Income Taxes		(199,589)
Future Net Cash Flows		2,434,914
10% Discount Factor		(1,556,927)
Standardized Measure of Discounted Future Net Cash Flows		$ 877,987			$ 881,544