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Supplemental Balance Sheet Information - Schedule of Activity in Asset Retirement Obligation (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]    
Asset retirement obligation, beginning balance $ 10,329 $ 2,587
Additions 281 281
Revision in estimate 0 7,205
Disposals (290) (124)
Expenditures (1,526) (671)
Accretion of discount 1,924 1,051
Asset retirement obligation, ending balance 10,718 10,329
Less: current portion of asset retirement obligations (1,021) (1,285)
Asset retirement obligations $ 9,697 $ 9,044