Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Condensed Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 20,945	$ 33,551	$ 66,181	$ 48,652
Foreign currency translations, net of tax	(250)	(296)	(968)	516
Comprehensive income	$ 20,695	$ 33,255	$ 65,213	$ 49,168