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Asset Retirement Obligations - Schedule of Activity in Asset Retirement Obligations (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]    
Balance as of January 1, 2019 $ 2,587 $ 2,507
Additions 281 16
Revision in estimate 7,205 0
Disposals (124) (148)
Expenditures (671) 0
Accretion of discount 1,051 212
Balance as of December 31, 2019 $ 10,329 $ 2,587