Income Taxes - Summary of Income Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current
Federal	$ (9,920)	$ 983	$ 44,887
State	(1,848)	(1,397)	(4,387)
Total	(11,768)	(414)	40,500
Deferred
Federal	(218,357)	(72,869)	(32,375)
State	(12,350)	(99)	(80,192)
Total	(230,707)	(72,968)	(112,567)
Income tax (benefit) expense	$ (242,475)	$ (73,382)	$ (72,067)