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Asset Retirement Obligations (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]    
Beginning asset retirement obligations $ 3,027  
Liabilities incurred 427  
Liabilities settled (15)  
Acquisitions 10,287  
Accretion expense 290 $ 44
Ending asset retirement obligations $ 14,016