Asset Retirement Obligations - Asset Retirement Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Jan. 31, 2019
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of year	$ 0
Liabilities incurred during the period	53,294
Liability settled during the period	(28,296)
Revisions in estimated cash flows	822
Accretion expense	2,438
Balance at end of year	28,258
Business Acquisition [Line Items]
ARO liability	$ 28,258
Droshky Prospect
Business Acquisition [Line Items]
ARO liability		$ 53,300
Other receivables		50,800
Acquired property		$ 2,500

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

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of asset retirement obligations incurred during the period.

+ References

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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.

+ References

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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

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

+ References

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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-Publisher FASB
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Amount due from parties in nontrade transactions, classified as other.

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