Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 64,047	$ 95,401	$ 81,241
Other comprehensive income (loss):
Foreign currency translation adjustments	(1,465)	(3,391)	(1,598)
Unrealized gain (loss) on investments, net of tax	21	(31)	1,369
Unrealized gain on derivative, net of tax	286	0	0
Other	(2)	(119)	(152)
Other comprehensive loss	(1,160)	(3,541)	(381)
Comprehensive income	$ 62,887	$ 91,860	$ 80,860