Shareholders' Equity (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Changes in Shareholders' Equity [Roll Forward]
Beginning balance	[1]	$ (44)
Net income		574	$ 583
Other comprehensive income (loss), net of tax		126	$ (339)
Ending balance		(73)
Accumulated other comprehensive income (loss), cumulative translation losses		2,962		$ 3,087
Accumulated other comprehensive income (loss), unrecognized retirement plan and other retiree benefits costs		857		$ 868
Common Stock
Changes in Shareholders' Equity [Roll Forward]
Beginning balance		1,466
Ending balance		1,466
Additional Paid-in Capital
Changes in Shareholders' Equity [Roll Forward]
Beginning balance		1,438
Stock-based compensation expense		31
Shares issued for stock options		45
Shares issued for restricted stock units		(23)
Other		4
Ending balance		1,495
Unearned Compensation
Changes in Shareholders' Equity [Roll Forward]
Beginning balance		(12)
Other		5
Ending balance		(7)
Treasury Stock
Changes in Shareholders' Equity [Roll Forward]
Beginning balance		(18,102)
Shares issued for stock options		104
Shares issued for restricted stock units		23
Treasury stock acquired		(229)
Ending balance		(18,204)
Retained Earnings
Changes in Shareholders' Equity [Roll Forward]
Beginning balance		18,861
Net income		533
Dividends		(689)
Ending balance		18,705
Accumulated Other Comprehensive Income (Loss)
Changes in Shareholders' Equity [Roll Forward]
Beginning balance		(3,950)
Other comprehensive income (loss), net of tax		125
Ending balance		(3,825)
Noncontrolling Interests
Changes in Shareholders' Equity [Roll Forward]
Beginning balance		255
Net income		41
Other comprehensive income (loss), net of tax		1
Ending balance		$ 297

[1] Prior year amounts have been reclassified to conform to the current year presentation of debt issuance costs required by Accounting Standards Update (“ASU”) No. 2015-03 “Simplifying the Presentation of Debt Issuance Costs.” See Note 1 to the Condensed Consolidated Financial Statements for additional information.