Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 23,178	$ 39,702	$ 63,124	$ 82,948
Other comprehensive income, before tax and net of reclassification adjustments:
Foreign currency translation adjustment	(3,789)	(9,909)	(14,273)	(10,467)
Unrealized (loss) gain on securities available-for-sale	(348)	(221)	441	(129)
Unrealized (loss) gain on derivative instruments	(7,642)	10,023	(14,378)	8,063
Other comprehensive loss, before tax	(11,779)	(107)	(28,210)	(2,533)
Tax expense related to items of other comprehensive income	(3,935)	5,224	(8,238)	4,584
Other comprehensive loss, net of tax	(7,844)	(5,331)	(19,972)	(7,117)
Comprehensive income	$ 15,334	$ 34,371	$ 43,152	$ 75,831