Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital	Unearned Compensation	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Beginning balance at Dec. 31, 2014		$ 1,466	$ 1,236	$ (20)	$ (16,862)	$ 18,832	$ (3,507)	$ 240
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 1,548					1,384		164
Other comprehensive income (loss), net of tax	(454)						(443)	(11)
Dividends						(1,355)		(138)
Stock-based compensation expense			125
Shares issued for stock options			90		243
Shares issued for restricted stock awards			(69)		69
Treasury stock acquired					(1,551)
Other			56	8	(1)
Ending balance at Dec. 31, 2015		1,466	1,438	(12)	(18,102)	18,861	(3,950)	255
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,586					2,441		145
Other comprehensive income (loss), net of tax	(242)						(230)	(12)
Dividends						(1,380)		(128)
Stock-based compensation expense			123
Shares issued for stock options			128		242
Shares issued for restricted stock awards			(60)		60
Treasury stock acquired					(1,335)
Other			62	5
Ending balance at Dec. 31, 2016	17	1,466	1,691	(7)	(19,135)	19,922	(4,180)	260
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,174					2,024		150
Other comprehensive income (loss), net of tax	342						325	17
Dividends						(1,405)		(124)
Stock-based compensation expense			127
Shares issued for stock options			197		313
Shares issued for restricted stock awards			(34)		34
Treasury stock acquired					(1,399)
Other			3	2	6	(10)
Ending balance at Dec. 31, 2017	$ 243	$ 1,466	$ 1,984	$ (5)	$ (20,181)	$ 20,531	$ (3,855)	$ 303