Tax (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Difference between the effective tax rate
Federal income tax at U.S. federal statutory rate	$ 310	$ 247	$ 616	$ 455
Foreign income tax rate differential	(57)	(41)	(80)	(65)
State income tax, net of federal benefit	9	5	17	11
Nondeductible expenses	10	14	23	24
Tax impact of foreign exchange	12		(18)
Tax benefit of manufacturing deduction	(9)	(6)	(18)	(12)
Foreign dividends, net of foreign tax credits	14	5	20	10
Tax rate change on temporary differences				(13)
Other	(4)	2	(6)	5
Income Tax Expense (Benefit)	$ 285	$ 226	$ 554	$ 415

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The sum of domestic current and deferred income tax expense or benefit attributable to continuing operations.

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