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Asset Retirement Obligations (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]    
Beginning asset retirement obligations $ 85,325 $ 86,846
Liabilities incurred (1) 1,715 1,018
Liabilities settled (2) (1,948) (1,404)
Accretion expense 4,159 4,034
Revision to estimated cash flows 12,173 (5,169)
Ending asset retirement obligations (3) 101,424 85,325
Current asset retirement obligation liability $ 4,100 $ 2,000