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
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 24,238	$ 18,191	$ 48,831	$ 35,666
Net cumulative translation adjustment and foreign currency exchange hedge, net of tax of $(166), $(91), $(160) and $(237), respectively	(266)	(147)	(316)	(381)
Net unrealized (loss) gain on securities available-for-sale, net of tax of $(43), $2, $(4) and $35, respectively	(69)	4	(6)	56
Less: reclassification adjustment for realized gain from securities available-for-sale included in Other Income, net of tax of $0, $0, $0 and $(13), respectively				(22)
Net change in unrealized (loss) gain on securities available-for-sale, net of tax	(69)	4	(6)	34
Comprehensive Income	$ 23,903	$ 18,048	$ 48,509	$ 35,319