Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Number of shares of common stock [Member]	Common stock and additional paid-in capital [Member]	Accumulated deficit [Member]	Accumulated other comprehensive loss [Member]
Beginning Balance, Shares at Dec. 31, 2017		722.2
Balance as of beginning of period at Dec. 31, 2017	$ 25,241		$ 30,992	$ (5,072)	$ (679)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income for basic and diluted EPS	2,311			2,311
Other comprehensive income (loss), net of taxes	(306)				(306)
Dividends declared on common stock	(877)			(877)
Issuance of common stock in connection with the Company’s equity award programs, Shares		0.6
Issuance of common stock in connection with the Company’s equity award programs	5		5
Stock-based compensation expense	61		61
Tax impact related to employee stock-based compensation expense	(57)		(57)
Repurchases of common stock, Shares		(56.4)
Repurchases of common stock	(10,787)			(10,787)
Ending Balance, Shares at Mar. 31, 2018		666.4
Balance as of end of period at Mar. 31, 2018	$ 15,620		31,001	(14,387)	(994)
Beginning Balance, Shares at Dec. 31, 2018	629.6	629.6
Balance as of beginning of period at Dec. 31, 2018	$ 12,500		31,246	(17,977)	(769)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income for basic and diluted EPS	1,992			1,992
Other comprehensive income (loss), net of taxes	253				253
Dividends declared on common stock	(879)			(879)
Issuance of common stock in connection with the Company’s equity award programs, Shares		0.7
Issuance of common stock in connection with the Company’s equity award programs	6		6
Stock-based compensation expense	64		64
Tax impact related to employee stock-based compensation expense	(73)		(73)
Repurchases of common stock, Shares		(15.9)
Repurchases of common stock	$ (3,031)			(3,031)
Ending Balance, Shares at Mar. 31, 2019	614.4	614.4
Balance as of end of period at Mar. 31, 2019	$ 10,832		$ 31,243	$ (19,895)	$ (516)