Income Taxes - Schedule of Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Federal	$ 20,553	$ 14,435	$ 15,324
State	2,933	1,275	2,227
Foreign	876	1,129	686
Deferred:
Federal	(3,051)	922	(2,568)
State	(915)	151	(353)
Foreign	(134)	(363)	(102)
Provision for income taxes	$ 20,262	$ 17,549	$ 15,214