Derivatives (Schedule of Price Risk Derivatives) (Details) T in Thousands	6 Months Ended
Jun. 30, 2022 T
2022 \| Coal sales
Derivative [Line Items]
Derivatives held (in tons)	116

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.

No definition available.

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