Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 48,105	$ 40,487	$ 100,627	$ 88,427
Net cumulative translation adjustment and foreign currency exchange hedge, net of tax of $721, $1,328, $269 and $506, respectively	(1,100)	(1,288)	18	(1,020)
Net unrealized gain (loss) on securities available-for-sale, net of tax of $144, $18, $287 and $(89), respectively	459	57	918	(277)
Comprehensive income	$ 47,464	$ 39,256	$ 101,563	$ 87,130