Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative effect adjustment for adoption of new accounting guidance	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Accumulated Deficit Cumulative effect adjustment for adoption of new accounting guidance
Beginning balance (in shares) at Dec. 31, 2018			255,172
Beginning balance at Dec. 31, 2018	$ 4,435,203	$ (40,310)	$ 2,546	$ 7,421,476	$ 659	$ (2,989,478)	$ (40,310)
Increase (Decrease) in Stockholders' Equity
Other comprehensive loss, net of tax	(3,860)				(3,860)
Net income	536,058					536,058
Repurchases of common stock (in shares)			(833)
Repurchase of common stock	(150,017)		$ (9)	(150,008)
Common stock withheld for employee tax obligations (in shares)			(27)
Common stock withheld for employee tax obligations	(5,832)			(5,832)
Issuance of common stock under benefit plans (in shares)			2,359
Issuance of common stock under benefit plans	114,545		$ 28	114,517
Stock-based compensation expense	184,178			184,178
Ending balance (in shares) at Jun. 30, 2019			256,671
Ending balance at Jun. 30, 2019	5,069,965		$ 2,565	7,564,331	(3,201)	(2,493,730)
Beginning balance (in shares) at Mar. 31, 2019			256,351
Beginning balance at Mar. 31, 2019	4,723,313		$ 2,561	7,475,909	6,000	(2,761,157)
Increase (Decrease) in Stockholders' Equity
Other comprehensive loss, net of tax	(9,201)				(9,201)
Net income	267,427					267,427
Repurchases of common stock (in shares)			(296)
Repurchase of common stock	(52,010)		$ (3)	(52,007)
Issuance of common stock under benefit plans (in shares)			616
Issuance of common stock under benefit plans	50,501		$ 7	50,494
Stock-based compensation expense	89,935			89,935
Ending balance (in shares) at Jun. 30, 2019			256,671
Ending balance at Jun. 30, 2019	5,069,965		$ 2,565	7,564,331	(3,201)	(2,493,730)
Beginning balance (in shares) at Dec. 31, 2019			258,993
Beginning balance at Dec. 31, 2019	6,085,244		$ 2,589	7,937,606	(1,973)	(1,852,978)
Increase (Decrease) in Stockholders' Equity
Other comprehensive loss, net of tax	(12,148)				(12,148)
Net income	1,440,023					1,440,023
Repurchases of common stock (in shares)			(1,404)
Repurchase of common stock	(300,026)		$ (14)	(300,012)
Common stock withheld for employee tax obligations (in shares)			(586)
Common stock withheld for employee tax obligations	(139,247)		$ (6)	(139,241)
Issuance of common stock under benefit plans (in shares)			3,121
Issuance of common stock under benefit plans	210,375		$ 32	210,343
Stock-based compensation expense	235,021			235,021
Ending balance (in shares) at Jun. 30, 2020			260,124
Ending balance at Jun. 30, 2020	7,519,242		$ 2,601	7,943,717	(14,121)	(412,955)
Beginning balance (in shares) at Mar. 31, 2020			259,079
Beginning balance at Mar. 31, 2020	6,461,654		$ 2,591	7,695,905	13,383	(1,250,225)
Increase (Decrease) in Stockholders' Equity
Other comprehensive loss, net of tax	(27,504)				(27,504)
Net income	837,270					837,270
Common stock withheld for employee tax obligations (in shares)			(11)
Common stock withheld for employee tax obligations	(3,080)			(3,080)
Issuance of common stock under benefit plans (in shares)			1,056
Issuance of common stock under benefit plans	132,781		$ 10	132,771
Stock-based compensation expense	118,121			118,121
Ending balance (in shares) at Jun. 30, 2020			260,124
Ending balance at Jun. 30, 2020	$ 7,519,242		$ 2,601	$ 7,943,717	$ (14,121)	$ (412,955)