Income Taxes - Summary of components of provision (benefit) for income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current (benefit) provision:
Federal	$ (43,993)	$ (24,727)	$ 119,074
State	(24,479)	(3,638)	19,858
Foreign	4,567	7,898	2,907
Deferred (benefit) provision:
Federal	(31,505)	(31,178)	11,514
State	(2,704)	(1,835)	840
Total income tax (benefit) provision	$ (98,114)	$ (53,480)	$ 154,193