Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 161,915	$ 113,915	$ 285,061	$ 221,045
Other comprehensive income (loss):
Foreign currency translation adjustments	5,808	2,849	(20,469)	3,351
Change in unrealized (loss) gain on investments, net of income tax benefit (provision) of $(5,144), $(547), $(3,679) and $(1,101) for the three and six months ended June 30, 2020 and 2019, respectively	15,880	1,646	8,306	3,077
Other comprehensive income (loss)	21,688	4,495	(12,163)	6,428
Comprehensive income	$ 183,603	$ 118,410	$ 272,898	$ 227,473