Tax (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Difference between the effective tax rate
Federal income tax at U.S. federal statutory rate	$ 306	$ 208
Foreign income tax rate differential	(23)	(24)
State income tax, net of federal benefit	8	6
Nondeductible expenses	13	10
Tax benefit of manufacturing deduction	(9)	(6)
Foreign dividends, net of foreign tax credits	6	5
Tax impact of foreign exchange	(30)
Tax rate change on temporary differences		(13)
Other	(2)	3
Total income tax provision	$ 269	$ 189

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The sum of foreign current income tax expense or benefit and foreign deferred income tax expense or benefit pertaining to Income or Loss from continuing foreign operations.

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