Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 17,176	$ 12,685	$ 26,863	$ 23,737
Other comprehensive income (loss):
Foreign currency translation adjustments	2,513	(832)	3,121	516
Unrealized gain (loss) on investments, net of tax	12	22	16	16
Unrealized gain (loss) on derivative, net of tax	(200)	(667)	165	(2,899)
Other	0	0	(13)	0
Other comprehensive income (loss)	2,325	(1,477)	3,289	(2,367)
Comprehensive income	$ 19,501	$ 11,208	$ 30,152	$ 21,370