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Asset Retirement Obligations - Schedule of Changes in Asset Retirement Obligations (Details)
$ in Thousands
3 Months Ended
Mar. 31, 2020
USD ($)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]  
December 31, 2019 $ 56,784
Liabilities incurred during period 333
Liabilities settled during period (194)
Accretion expense during period 765
March 31, 2020 $ 57,688