Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 33,126	$ 24,238	$ 62,089	$ 48,831
Net cumulative translation adjustment and foreign currency exchange hedge, net of tax of $2,089, $(166), $4,101 and $(160), respectively	(1,804)	(266)	(4,041)	(316)
Net unrealized gain (loss) on securities available-for-sale, net of tax of $21, $(43), $136 and $(4), respectively	34	(69)	221	(6)
Comprehensive Income	$ 31,356	$ 23,903	$ 58,269	$ 48,509