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Asset Retirement Obligations - Schedule of Change in Asset Retirement Obligations (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Asset Retirement Obligation [Abstract]    
Asset retirement obligations at beginning of period $ 7,488 $ 6,835
Wells drilled during the year 154 331
Wells acquired during the year 28 176
Wells sold during the year (4,780) (5)
Accretion of discount 180 214
Revisions of previous estimates (205) 13
Wells plugged and abandoned during the year (182) (76)
Asset retirement obligations at end of period $ 2,683 $ 7,488