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Asset Retirement Obligations - Schedule of Changes in Asset Retirement Obligations (Details)
$ in Thousands
3 Months Ended
Mar. 31, 2021
USD ($)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]  
Balance at beginning of period $ 48,594
Liabilities incurred during period 4
Accretion expense during period 1,032
Balance at end of period $ 49,630