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Derivative Instruments - Textual (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
Derivatives, Fair Value [Line Items]          
Accumulated other comprehensive income (loss) $ 303   $ 303   $ (4,750)
Gain (loss) to be reclassified     300    
Gas hedges          
Derivatives, Fair Value [Line Items]          
Gain or loss recognized in oil and gas contracts $ 618 $ (144) $ 404 $ 2,043