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Business and Basis of Presentation (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]        
Idle mine costs $ 9,327 $ 0 $ 20,203 $ 0
Business interruption costs $ 6,872 $ 0 $ 13,892 $ 0