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Marshall Mine (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2023
Jun. 30, 2022
Jun. 30, 2023
Jun. 30, 2022
Mar. 27, 2023
Business Acquisition [Line Items]          
Gain on change in estimate, asset retirement obligation $ 0 $ 0 $ 2,695 $ 0  
Marshall Mine          
Business Acquisition [Line Items]          
Consideration         $ 2,200
Liabilities         $ 4,900
Gain on change in estimate, asset retirement obligation     $ 2,700