Consolidated Statement of Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Statement of Other Comprehensive Income [Abstract]
Foreign currency translation, net of tax (provision)/benefit	$ (21)	$ 17
Current year actuarial gain (loss), net of tax (provision)/benefit	(10)	(6)
Amortization of actuarial (gain) loss, net of tax (provision)/benefit	(67)	(60)
Current year prior service credit (cost), net of tax (provision)/benefit	0	2
Amortization of prior service (credit) cost, net of tax (provision)/benefit	5	4
Amortization of transition (asset) obligation, net of tax (provision)/benefit	0	0
Derivative financial instruments, Gains (losses) deferred, net of tax (provision)/benefit	18	16
Derivative financial instruments, (Gains) losses reclassified to earnings, net of tax (provision)/benefit	(7)	1
Available-for-sale securities, Gains (losses) deferred, net of tax (provision)/benefit	(8)	(9)
Available-for-sale securities, (Gains) losses reclassified to earnings, net of tax (provision)/benefit	$ 0	$ 0

Tax effect of the income statement impact of the reclassification adjustment for prior service costs recognized as a component of net period benefit cost.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Paragraph 38

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Tax effect of unrealized holding gain (loss) before reclassification adjustments and transfers on available-for-sale securities.

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