Derivative Instruments - Schedule of Location and Fair Value of Outstanding Commodity Derivative Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative instruments — current assets	$ 9,142	$ 139,697
Derivative instruments — non-current assets	194	15,776
Derivative instruments — current liabilities	(17,308)	0
Derivative instruments — non-current liabilities	(7,755)	0
Commodity derivative instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative instruments — current assets	9,142	139,697
Derivative instruments — non-current assets	194	15,776
Derivative instruments — current liabilities	(17,308)	0
Derivative instruments — non-current liabilities	(7,755)	0
Total derivative instruments	$ (15,727)	$ 155,473