Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 158,623	$ 137,890	$ 443,684	$ 358,935
Other comprehensive income (loss):
Foreign currency translation adjustments	13,177	(14,095)	(7,292)	(10,744)
Change in unrealized (loss) gain on investments, net of income tax benefit (provision) of $559, $(52), $(3,120) and $(1,153) for the three and nine months ended September 30, 2020 and 2019, respectively	(1,724)	155	6,582	3,232
Other comprehensive income (loss)	11,453	(13,940)	(710)	(7,512)
Comprehensive income	$ 170,076	$ 123,950	$ 442,974	$ 351,423