Summary of Significant Accounting Policies - Summary of Changes in Reserve for Future Abandonment Costs (Detail) - USD ($) $ in Thousands	5 Months Ended	7 Months Ended	12 Months Ended
Dec. 31, 2018	Aug. 13, 2018	Dec. 31, 2019
Asset Retirement Obligations Noncurrent [Abstract]
Reserve for future abandonment costs at beginning of the year	$ 4,683		$ 5,136
Wells acquired			5,700
New wells placed on production	50		516
Changes in estimates and timing	270		6,333
Liabilities settled			(57)
Asset divestitures			(45)
Accretion expense	133		568
Reserve for future abandonment costs at end of the year	5,136	$ 4,683	$ 18,151
Predecessor
Asset Retirement Obligations Noncurrent [Abstract]
Reserve for future abandonment costs at beginning of the year	$ 10,683	10,407
New wells placed on production		17
Liabilities settled		(87)
Accretion expense		346
Reserve for future abandonment costs at end of the year		$ 10,683

Asset retirement obligation disposed.

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- Definition

Asset retirement obligation liabilities for wells acquired.

+ References

No definition available.

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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Amount of asset retirement obligations incurred during the period.

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 35
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6392603&loc=d3e7123-110846

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-Publisher FASB
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-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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