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Asset Retirement Obligations (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]    
Beginning asset retirement obligations $ 2,164 $ 2,229
Liabilities incurred 106 105
Property dispositions (10) (10)
Liabilities settled (195) (374)
Accretion expense 307 214
Revision of estimates 655 0
Ending asset retirement obligations 3,027 2,164
Asset retirement obligation $ 2,164 $ 2,164