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Asset Retirement Obligations - Summary of Changes in Asset Retirement Obligations (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]        
Asset retirement obligations, beginning of period     $ 18,220  
Additional liabilities incurred     1,803  
Accretion expense $ 190 $ 187 575 $ 657
Liabilities settled upon plugging and abandoning wells     (6)  
Disposition of wells     (534)  
Revision of estimates     (2,927)  
Asset retirement obligations, end of period $ 17,131   $ 17,131