Income Taxes - Provision for Income Tax (Benefit) Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
Federal	$ (1,377)	$ 69,245	$ 349
State	(138)	135	169
Total	(1,515)	69,380	518
Deferred:
Federal	2,261	35,314	(366)
State	62	10,813	(561)
Total	2,323	46,127	(927)
Income tax expense (benefit)	$ 808	$ 115,507	$ (409)