Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 126,172	$ 96,037	$ 74,806
Net cumulative translation adjustment and foreign currency exchange hedge, net of tax of $5,407, $(258) and $(275), respectively	(7,037)	(512)	(399)
Net unrealized gain (loss) on securities available-for-sale, net of tax of $24, $(111), and $(9), respectively	38	(180)	(16)
Less: reclassification adjustment for realized gain on the sale of securities available-for-sale included in Other Income, net of tax of $(0), $(0) and $(24), respectively			(39)
Net change in unrealized gain (loss) on securities available-for-sale, net of tax	38	(180)	(55)
Comprehensive income	$ 119,173	$ 95,345	$ 74,352