The amount of asset impairment charges and mine closure costs during the period.

No definition available.

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- Definition

Represents information pertaining to number of corporate staff accepted voluntary separation package.

+ References

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=126905981&loc=d3e2420-110228

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- Definition

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.

+ Details

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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

+ References

+ Details

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Asset Impairment and Restructuring (Details) $ in Thousands	3 Months Ended		6 Months Ended	12 Months Ended
Asset Impairment and Restructuring (Details) $ in Thousands	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 item	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Property, Plant and Equipment [Line Items]
Severance Costs				$ 0	$ 0	$ 13,400
Number of corporate staff accepted voluntary separation package \| item			254
Asset Impairment Charges And Mine Closure Costs						$ 221,380
Knight Hawk
Property, Plant and Equipment [Line Items]
Asset impairment charges		$ 36,200
Prior Equity Investment
Property, Plant and Equipment [Line Items]
Asset Impairment Charges And Mine Closure Costs	$ 10,000
Coal Creek Mine
Property, Plant and Equipment [Line Items]
Asset impairment charges		51,800
Asset Impairment Charges And Mine Closure Costs	$ 32,800
Viper Mine
Property, Plant and Equipment [Line Items]
Asset impairment charges		33,500
West Elk Mine
Property, Plant and Equipment [Line Items]
Asset impairment charges		$ 41,600