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Asset Retirement Obligations - Schedule of Changes in Asset Retirement Obligations (Details)
$ in Thousands
6 Months Ended
Jun. 30, 2021
USD ($)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]  
Balance at beginning of period $ 48,594
Liabilities incurred during period 401
Liabilities settled during period (322)
Accretion expense during period 2,043
Revisions to estimates 193
Liabilities settled through divestitures (4,845)
Balance at end of period $ 46,064