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Business and Basis of Presentation (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]        
Idle mine costs $ 10,876 $ 0 $ 10,876 $ 0
Business interruption costs $ 7,020 $ 0 $ 7,020 $ 0