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Asset Retirement Obligations - Asset Retirement Obligations (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]      
AROs at beginning of year $ 30,913 $ 28,258  
Liability incurred during the period     $ 53,294
Liability settled during the period     (28,296)
Revisions in estimates (2,631)   822
Accretion expense 1,376 2,655 2,438
AROs at end of period $ 29,658 $ 30,913 $ 28,258