Shareholders' Equity (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Changes in Shareholders' Equity [Roll Forward]
Beginning balance	$ 1,385
Net income	583	432
Other comprehensive income, net of tax	(339)	(87)
Ending balance	739
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	2,805		2,453
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax	1,051		1,064
Common Stock [Member]
Changes in Shareholders' Equity [Roll Forward]
Beginning balance			1,466
Ending balance	1,466		1,466
Additional Paid-In Capital [Member]
Changes in Shareholders' Equity [Roll Forward]
Beginning balance	1,236
Stock-based compensation expense	32
Shares issued for stock options	32
Stock issued for restricted stock awards	(29)
Other	1
Ending balance	1,272
Unearned Compensation [Member]
Changes in Shareholders' Equity [Roll Forward]
Beginning balance	(20)
Other	7
Ending balance	(13)
Treasury Stock [Member]
Changes in Shareholders' Equity [Roll Forward]
Beginning balance	(16,862)
Shares issued for stock options	85
Stock issued for restricted stock awards	29
Treasury stock acquired	(374)
Ending balance	(17,122)
Retained Earnings [Member]
Changes in Shareholders' Equity [Roll Forward]
Beginning balance	18,832
Net income	542
Dividends	(670)
Ending balance	18,704
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in Shareholders' Equity [Roll Forward]
Beginning balance	(3,507)
Other comprehensive income, net of tax	(340)
Ending balance	(3,847)
Noncontrolling Interests [Member]
Changes in Shareholders' Equity [Roll Forward]
Beginning balance	240
Net income	41
Other comprehensive income, net of tax	1
Dividends	(3)
Ending balance	$ 279