Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Federal:
Current	$ 91,015	$ 59,792	$ 61,688
Deferred	17,345	48,962	8,394
Federal, Total	108,360	108,754	70,082
State:
Current	18,633	13,584	12,965
Deferred	2,747	9,184	1,013
State, Total	21,380	22,768	13,978
Foreign:
Current	7,793	5,445	3,372
Deferred	(1,753)	(1,424)	(554)
Foreign, Total	6,040	4,021	2,818
Total income tax expense (benefit)	$ 135,780	$ 135,543	$ 86,878