Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 9,687	$ 11,052
Other comprehensive loss:
Foreign currency translation adjustments	608	1,348
Unrealized gain (loss) on investments, net of tax	4	(6)
Unrealized gain (loss) on derivative, net of tax	365	(2,232)
Other	(13)	0
Other comprehensive loss	964	(890)
Comprehensive income	$ 10,651	$ 10,162