Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net income	$ 4,314	$ 5,042	$ 16,918	$ 12,893
Other comprehensive income (loss):
Foreign currency translation adjustment, net	(308)	664	(1,204)	2,303
Unrealized gain (loss) on short-term marketable securities	33		11
Total other comprehensive income (loss)	(275)	664	(1,193)	2,303
Comprehensive income	$ 4,039	$ 5,706	$ 15,725	$ 15,196