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Asset Retirement Obligation
12 Months Ended
Dec. 31, 2021
Asset Retirement Obligation Disclosure [Abstract]  
Asset Retirement Obligation Asset Retirement ObligationThe Company had a post-closure reclamation and site restoration obligation of $16,155 as of December 31, 2021. The following is a reconciliation of the total reclamation liability for asset retirement obligations.
Balance at December 31, 2019$6,142 
Additions and revisions of prior estimates8,458 
Accretion expenses396 
Settlement of liability— 
Balance at December 31, 2020$14,996 
Additions and revisions of prior estimates419 
Accretion expenses740 
Settlement of liability— 
Balance at December 31, 2021$16,155