Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Accumulated Other Comprehensive Loss	Retained Earnings (Accumulated Deficit)
Common Stock, Shares, Outstanding		119,063
Common stock and additional paid-in capital	$ 4,687,455
Stockholders' Equity Attributable to Parent	4,359,679
Accumulated Other Comprehensive Income (Loss), Net of Tax	(6,624)
Retained Earnings (Accumulated Deficit)	(321,152)
Net income	122,579	$ 0	$ 0	$ 122,579
Other Comprehensive Income (Loss), Net of Tax	(1,034)	$ 0	(1,034)	0
Exercise Of Stock Options And Vesting Of Restricted Stock Units Net Of Shares Withheld For Employee Taxes Shares		837
Exercise Of Stock Options And Vesting Of Restricted Stock Units Net Of Shares Withheld For Employee Taxes	(15,609)	$ (15,609)	0	0
Stock Issued During Period, Shares, Employee Stock Purchase Plans		239
Stock Issued During Period, Value, Employee Stock Purchase Plan	14,948	$ 14,948	0	0
Cumulative-effect adoption of ASU 2016-02	$ 69	$ 0	0	69
Stock Repurchased During Period, Shares	(3,800)	(3,845)
Stock Repurchased During Period, Value	$ (265,105)	$ (265,105)	0	0
Stock-based compensation	49,967	$ 49,967	0	0
Payments for Repurchase of Common Stock	265,105
Common Stock, Shares, Outstanding		117,943
Common stock and additional paid-in capital	4,625,566
Stockholders' Equity Attributable to Parent	4,337,343
Accumulated Other Comprehensive Income (Loss), Net of Tax	(6,681)
Retained Earnings (Accumulated Deficit)	(281,542)
Net income	83,038	$ 0	0	83,038
Other Comprehensive Income (Loss), Net of Tax	(977)	$ 0	(977)	0
Exercise Of Stock Options And Vesting Of Restricted Stock Units Net Of Shares Withheld For Employee Taxes Shares		652
Exercise Of Stock Options And Vesting Of Restricted Stock Units Net Of Shares Withheld For Employee Taxes	$ (12,033)	$ (12,033)	0	0
Stock Repurchased During Period, Shares	(2,300)	(2,301)
Stock Repurchased During Period, Value	$ (165,032)	$ (165,032)	0	0
Stock-based compensation	23,155	$ 23,155	0	0
Common Stock, Shares, Outstanding		116,294
Common stock and additional paid-in capital	4,471,656
Stockholders' Equity Attributable to Parent	4,265,494
Accumulated Other Comprehensive Income (Loss), Net of Tax	(7,658)
Retained Earnings (Accumulated Deficit)	$ (198,504)
Common Stock, Shares, Outstanding	114,625
Common stock and additional paid-in capital	$ 4,290,377
Stockholders' Equity Attributable to Parent	4,292,665
Accumulated Other Comprehensive Income (Loss), Net of Tax	2,288
Retained Earnings (Accumulated Deficit)	0
Net income	233,839	$ 0	0	233,839
Other Comprehensive Income (Loss), Net of Tax	24,328	$ 0	24,328	0
Exercise Of Stock Options And Vesting Of Restricted Stock Units Net Of Shares Withheld For Employee Taxes Shares		826
Exercise Of Stock Options And Vesting Of Restricted Stock Units Net Of Shares Withheld For Employee Taxes	(32,371)	$ (32,371)	0	0
Stock Issued During Period, Shares, Employee Stock Purchase Plans		229
Stock Issued During Period, Value, Employee Stock Purchase Plan	15,758	$ 15,758	0	0
Cumulative-effect adoption of ASU 2016-13	$ (38)	$ 0	0	(38)
Stock Repurchased During Period, Shares	(1,600)	(1,569)
Stock Repurchased During Period, Value	$ (180,048)	$ (58,830)	0	(121,218)
Stock-based compensation	53,053	53,053	0	0
Other Retained Earnings Adjustment	(20)	$ 0	0	(20)
Payments for Repurchase of Common Stock	180,048
Common Stock, Shares, Outstanding		114,354
Common stock and additional paid-in capital	4,293,621
Stockholders' Equity Attributable to Parent	4,351,245
Accumulated Other Comprehensive Income (Loss), Net of Tax	8,394
Retained Earnings (Accumulated Deficit)	49,230
Net income	136,917	$ 0	0	136,917
Other Comprehensive Income (Loss), Net of Tax	18,222	$ 0	18,222	0
Exercise Of Stock Options And Vesting Of Restricted Stock Units Net Of Shares Withheld For Employee Taxes Shares		594
Exercise Of Stock Options And Vesting Of Restricted Stock Units Net Of Shares Withheld For Employee Taxes	$ (26,306)	$ (26,306)	0	0
Stock Repurchased During Period, Shares	(800)	(837)
Stock Repurchased During Period, Value	$ (105,009)	$ (31,425)	0	(73,584)
Stock-based compensation	$ 32,097	$ 32,097	$ 0	$ 0
Common Stock, Shares, Outstanding	114,111
Common stock and additional paid-in capital	$ 4,267,987
Stockholders' Equity Attributable to Parent	4,407,166
Accumulated Other Comprehensive Income (Loss), Net of Tax	26,616
Retained Earnings (Accumulated Deficit)	$ 112,563