Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Treasury Stock	Retained Earnings (Accumulated Deficit)
Beginning balance (in shares) at Dec. 31, 2019		162,000,843
Beginning Balance at Dec. 31, 2019	$ 3,657,958	$ 1,620	$ 3,653,486	$ (45,144)	$ 0	$ 47,996
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon the exercise of stock options and vesting of restricted and deferred stock units, net of shares withheld for employee taxes (in shares)		1,047,040
Issuance of common stock upon the exercise of stock options and vesting of restricted and deferred stock units, net of shares withheld for employee taxes	(50,700)	$ 11	(50,711)
Stock-based compensation	56,215		56,215
Repurchases of common stock (in shares)		(871,294)
Repurchases of common stock	(80,550)				(80,550)
Net income	123,146					123,146
Foreign currency translation adjustments	(26,277)			(26,277)
Change in unrealized gain (loss) on investments, net of tax	(7,574)			(7,574)
Ending balance (in shares) at Mar. 31, 2020		162,176,589
Ending Balance at Mar. 31, 2020	3,672,218	$ 1,631	3,658,990	(78,995)	(80,550)	171,142
Beginning balance (in shares) at Dec. 31, 2020		162,709,720
Beginning Balance at Dec. 31, 2020	4,251,296	$ 1,627	3,664,820	(20,201)	0	605,050
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon the exercise of stock options and vesting of restricted and deferred stock units, net of shares withheld for employee taxes (in shares)		1,128,184
Issuance of common stock upon the exercise of stock options and vesting of restricted and deferred stock units, net of shares withheld for employee taxes	(64,006)	$ 11	(64,017)
Stock-based compensation	63,765		63,765
Repurchases of common stock (in shares)		(591,963)
Repurchases of common stock	(58,241)				(58,241)
Net income	155,695					155,695
Foreign currency translation adjustments	(24,265)			(24,265)
Change in unrealized gain (loss) on investments, net of tax	(2,881)			(2,881)
Ending balance (in shares) at Mar. 31, 2021		163,245,941
Ending Balance at Mar. 31, 2021	$ 4,321,363	$ 1,638	$ 3,664,568	$ (47,347)	$ (58,241)	$ 760,745