Derivatives - Schedule of price risk derivatives (Details) - Coal sales T in Thousands	9 Months Ended
Sep. 30, 2022 T
Derivative [Line Items]
Derivatives held (in tons)	79
2022
Derivative [Line Items]
Derivatives held (in tons)	39
2023
Derivative [Line Items]
Derivatives held (in tons)	40

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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