Asset Retirement Obligations - Asset Retirement Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 19, 2018
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning of period	$ 29,655	$ 17,586	$ 11,238
Liabilities incurred	2,863	10,649	10,683
Liabilities settled	(1,682)	(1,630)	(1,063)
Disposition of properties	(7,668)	(351)	(5,138)
Accretion expense	1,592	1,291	972
Revisions to estimate	949	2,110	894
End of period	25,709	29,655	17,586
Less: Current asset retirement obligations	2,218	2,325	1,489
Long-term asset retirement obligations	$ 23,491	$ 27,330	16,097
Asset Retirement Obligations Acquisition of Properties			$ 8,700	$ 7,400

Asset Retirement Obligation Non Current

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- Definition

Asset Retirement Obligations Acquisition of Properties

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No definition available.

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- Definition

Asset Retirement Obligations Disposition Of Properties

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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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- Definition

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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- Definition

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
-Topic 410
-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

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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