Asset Retirement Obligations (Details) - USD ($) $ in Thousands	1 Months Ended	8 Months Ended	9 Months Ended
Feb. 08, 2018	Sep. 30, 2018	Sep. 30, 2019	Dec. 31, 2018
Asset Retirement Obligation [Line Items]
Balance, beginning of period		$ 0	$ 11,552
Liabilities assumed in Business Combination		5,998	0
Liabilities incurred		1,689	831
Liabilities settled		(1,249)	(180)
Liabilities transferred in sale of properties		(20)	0
Revisions to estimates		3,562	19
Accretion expense		489	720
Balance, end of period	$ 0	10,469	12,942
Less: current portion		1,300	74	$ 2,079
Long-term portion		9,169	$ 12,868	$ 9,473
Predecessor
Asset Retirement Obligation [Line Items]
Balance, beginning of period	10,469	$ 10,509
Liabilities assumed in Business Combination	0
Liabilities incurred	0
Liabilities settled	(63)
Liabilities transferred in sale of properties	0
Revisions to estimates	63
Accretion expense	40
Balance, end of period	10,509
Less: current portion	33
Long-term portion	$ 10,476

Asset Retirement Obligation, Liabilities Assumed In Business Combination

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- Definition

Asset Retirement Obligation, Liabilities Transferred In Sale of Properties

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No definition available.

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- Definition

Asset Retirement Obligation [Line Items]

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- Definition

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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- 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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Current 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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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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- Definition

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
-Name Accounting Standards Codification
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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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