Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 21,210	$ 22,150	$ 35,415	$ 41,275
Other comprehensive loss:
Foreign currency translation adjustments	698	(206)	(2,764)	(233)
Unrealized gain (loss) on investments, net of tax	(38)	(145)	(33)	(154)
Other	(3)	(7)	(7)	(15)
Other comprehensive loss	657	(358)	(2,804)	(402)
Comprehensive income	$ 21,867	$ 21,792	$ 32,611	$ 40,873