Condensed Consolidated Statement of Stockholders' Equity - USD ($) $ in Millions	Total	Common Stock Outstanding	Treasury Shares at Cost	Par Value and Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Balance, beginning of period at Dec. 31, 2018	$ 24,718		$ (6)	$ 38,010	$ (332)	$ (12,954)
Common stock outstanding, beginning balance (in shares) at Dec. 31, 2018		850,180,317
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	908					908
Other comprehensive (loss) income	(189)				(189)
Stock-based compensation	121			121
Exercise of stock options	1			1
Exercise of stock options (in shares)		31,874
Stock issued for employee stock purchase plan	69			69
Stock issued for employee stock purchase plan (in shares)		1,172,511
Issuance of vested restricted stock units (in shares)		4,343,972
Shares withheld related to net share settlement of stock awards and stock options	(100)			(100)
Shares withheld related to net share settlement of stock awards and stock options (in shares)		(1,364,621)
Distribution from NQDC plan			1	(1)
Distribution from NQDC plan (in shares)		16,065
Prior year Retained Earnings	653					653
Balance, end of period at Mar. 31, 2019	26,181		(5)	38,100	(521)	(11,393)
Common stock outstanding, ending balance (in shares) at Mar. 31, 2019		854,380,118
Balance, beginning of period at Dec. 31, 2019	$ 28,789		(8)	38,498	(868)	(8,833)
Common stock outstanding, beginning balance (in shares) at Dec. 31, 2019	856,905,400	856,905,400
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 951					951
Other comprehensive (loss) income	(792)				(792)
Executive put option	1			1
Executive put option (in shares)		(342,000)
Stock-based compensation	152			152
Exercise of stock options	1			1
Exercise of stock options (in shares)		49,193
Stock issued for employee stock purchase plan	83			83
Stock issued for employee stock purchase plan (in shares)		1,246,317
Issuance of vested restricted stock units (in shares)		4,755,209
Shares withheld related to net share settlement of stock awards and stock options	(141)			(141)
Shares withheld related to net share settlement of stock awards and stock options (in shares)		(1,490,399)
Transfer RSU from NQDC plan			(3)	3
Transfer RSU to NQDC plan (in shares)		4,386
Prior year Retained Earnings	(67)					(67)
Balance, end of period at Mar. 31, 2020	$ 28,977		$ (11)	$ 38,597	$ (1,660)	$ (7,949)
Common stock outstanding, ending balance (in shares) at Mar. 31, 2020	861,128,106	861,128,106