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Asset Retirement Obligations - Schedule of Change in Asset Retirement Obligation Liability (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]      
Beginning asset retirement obligations $ 15,475 $ 14,509  
Liabilities incurred 209 245  
Liabilities settled (1,073) (129)  
Accretion expense 1,117 1,103 $ 1,026
Revisions in estimated costs 976 (16)  
Dispositions (620) (237)  
Ending asset retirement obligations 16,084 15,475 $ 14,509
Current asset retirement obligations 431 527  
Non-current asset retirement obligations $ 15,653 $ 14,948