Tax (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Difference between the effective tax rate
Federal income tax at U.S. federal statutory rate	$ 247	$ 205	$ 455	$ 420
Foreign income tax rate differential	(41)	(18)	(65)	(58)
State income tax, net of federal benefit	5	5	11	7
Nondeductible expenses	14	5	24	24
Tax benefit of manufacturing deduction	(6)	(3)	(12)	(6)
Foreign dividends, net of foreign tax credits	5	6	10	7
Tax rate change on temporary differences			(13)
Change in uncertain tax positions and other	2	(14)	5	(11)
Income Tax Expense (Benefit)	$ 226	$ 186	$ 415	$ 383

Difference between the effective tax rate.

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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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