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Asset Retirement Obligations - Summary of Asset Retirement Obligation (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Dec. 31, 2016
Asset Retirement Obligation Disclosure [Abstract]      
Balance, beginning of period $ 4,894 $ 4,468 $ 4,468
Liabilities settled (14)   (54)
Liabilities disposed (105)  
Accretion expense 132 $ 120 480
Balance, end of period 4,907   4,894
Less: Current portion (121)   (121)
Less: Included in liabilities held for sale   (105)
Non-current Portion $ 4,786   $ 4,668