Condensed 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, 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	1,328			1,328
Other comprehensive income (loss)	(229)			(4)	(225)
Common stock repurchases	(294)		200			(494)
Dividends and dividend equivalents	(208)			(208)
Stock-based compensation	105		105
Restricted stock unit vesting	0	$ 0	(92)			92
Restricted stock unit vesting (in shares)		0
Stock option exercises	49	$ 0	49			0
Stock option exercises (in shares)		21
Balances at Sep. 30, 2018	10,593	$ 33	2,707	14,786	(206)	(6,727)
Balances (in shares) at Sep. 30, 2018		198,593
Balances at Jun. 30, 2018	10,211	$ 33	2,672	14,211	(176)	(6,529)
Balances (in shares) at Jun. 30, 2018		198,591
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	644			644
Other comprehensive income (loss)	(30)				(30)
Common stock repurchases	(201)		0			(201)
Dividends and dividend equivalents	(69)			(69)
Stock-based compensation	35		35
Restricted stock unit vesting	0	$ 0	(3)			3
Restricted stock unit vesting (in shares)		0
Stock option exercises	3	$ 0	3			0
Stock option exercises (in shares)		2
Balances at Sep. 30, 2018	10,593	$ 33	2,707	14,786	(206)	(6,727)
Balances (in shares) at Sep. 30, 2018		198,593
Balances at Dec. 31, 2018	10,161	$ 33	2,535	15,072	(159)	(7,320)
Balances (in shares) at Dec. 31, 2018		198,595
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,195			2,195
Other comprehensive income (loss)	336				336
Common stock repurchases	(1,010)		(50)			(960)
Dividends and dividend equivalents	(222)			(222)
Stock-based compensation	119		119
Restricted stock unit vesting	0	$ 0	(3)			3
Restricted stock unit vesting (in shares)		32
Stock option exercises	22	$ 0	7			15
Stock option exercises (in shares)		2
Balances at Sep. 30, 2019	11,601	$ 33	2,608	17,045	177	(8,262)
Balances (in shares) at Sep. 30, 2019		198,629
Balances at Jun. 30, 2019	11,872	$ 33	2,763	16,429	112	(7,465)
Balances (in shares) at Jun. 30, 2019		198,628
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	689			689
Other comprehensive income (loss)	65				65
Common stock repurchases	(1,000)		(200)			(800)
Dividends and dividend equivalents	(73)			(73)
Stock-based compensation	43		43
Restricted stock unit vesting	0	$ 0				0
Restricted stock unit vesting (in shares)		0
Stock option exercises	5	$ 0	2			3
Stock option exercises (in shares)		1
Balances at Sep. 30, 2019	$ 11,601	$ 33	$ 2,608	$ 17,045	$ 177	$ (8,262)
Balances (in shares) at Sep. 30, 2019		198,629