Basis of Presentation - Schedule of Other Liabilities (Long-term) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Total other liabilities (long-term)	$ 83,814	$ 32,938
Other liabilities (long-term)
Dispute related to royalty deductions	5,247	5,467
Derivatives instruments - open contracts, long-term	55,467	4,384
Lease liability	11,190	11,360
Black Elk escrow	11,102	11,103
Other	$ 808	$ 624

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
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Amount of expenses incurred but not yet paid classified as other, due after one year or the normal operating cycle, if longer.

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Represents disputes related to deductions in royalties payable after one year or beyond the normal operating cycle, if longer.

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Amount of liabilities classified as escrow, due after one year or the normal operating cycle, if longer.

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