Consolidated Statements Of Stockholders' Equity - USD ($) shares in Thousands, $ in Millions	Total	Common Stock	Capital In Excess of Par Value	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Balances at Dec. 31, 2015	$ 10,346	$ 33	$ 2,530	$ 11,017	$ 58	$ (3,292)
Balances (in shares) at Dec. 31, 2015		198,372
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	614			614
Other comprehensive income (loss)	(124)				(124)
Common stock repurchases	(104)					(104)
Dividends and dividend equivalents	(177)			(177)
Stock-based compensation	115		115
Restricted stock unit vesting	0		(98)			98
Restricted stock unit vesting (in shares)		13
Stock option exercises	13		13
Stock option exercises (in shares)		110
Stock option and restricted stock tax benefit	2		2
Balances at Dec. 31, 2016	10,685	$ 33	2,562	11,454	(66)	(3,298)
Balances (in shares) at Dec. 31, 2016		198,495
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,448			2,448
Other comprehensive income (loss)	85				85
Common stock repurchases	(3,365)		(200)			(3,165)
Dividends and dividend equivalents	(232)			(232)
Stock-based compensation	157		157
Restricted stock unit vesting	0		(138)			138
Restricted stock unit vesting (in shares)		0
Stock option exercises	64		64
Stock option exercises (in shares)		77
Balances at Dec. 31, 2017	9,842	$ 33	2,445	13,670	19	(6,325)
Balances (in shares) at Dec. 31, 2017		198,572
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,683			1,683
Other comprehensive income (loss)	(174)
Other comprehensive loss	(182)			(4)	(178)
Common stock repurchases	(1,090)		50			(1,140)
Dividends and dividend equivalents	(277)			(277)
Stock-based compensation	137		137
Restricted stock unit vesting	0		(145)			145
Stock option exercises	$ 48		48
Stock option exercises (in shares)	320	23
Balances at Dec. 31, 2018	$ 10,161	$ 33	$ 2,535	$ 15,072	$ (159)	$ (7,320)
Balances (in shares) at Dec. 31, 2018		198,595