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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

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- Definition Business Interruption + References No definition available. + Details
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- Definition Idle Mine + References No definition available. + Details
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Balance Type: | debit
Period Type: | duration

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- References No definition available. + Details
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