Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings (Accumulated Deficit)
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 income, net of tax	15,356			15,356
Net income	602,753				602,753
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)		(575)
Common stock withheld for employee tax obligations	(136,167)	$ (6)	(136,161)
Issuance of common stock under benefit plans (in shares)		2,065
Issuance of common stock under benefit plans	77,594	$ 22	77,572
Stock-based compensation expense	116,900		116,900
Ending balance (in shares) at Mar. 31, 2020		259,079
Ending balance at Mar. 31, 2020	6,461,654	$ 2,591	7,695,905	13,383	(1,250,225)
Beginning balance (in shares) at Dec. 31, 2020		259,890
Beginning balance at Dec. 31, 2020	8,686,815	$ 2,599	7,894,027	(68,480)	858,669
Increase (Decrease) in Stockholders' Equity
Other comprehensive income, net of tax	35,178			35,178
Net income	653,138				653,138
Repurchases of common stock (in shares)		(1,989)
Repurchase of common stock	(424,952)	$ (20)	(424,932)
Common stock withheld for employee tax obligations (in shares)		(472)
Common stock withheld for employee tax obligations	(102,140)	$ (5)	(102,135)
Issuance of common stock under benefit plans (in shares)		1,400
Issuance of common stock under benefit plans	15,178	$ 14	15,164
Stock-based compensation expense	117,037		117,037
Ending balance (in shares) at Mar. 31, 2021		258,829
Ending balance at Mar. 31, 2021	$ 8,980,254	$ 2,588	$ 7,499,161	$ (33,302)	$ 1,511,807