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Tax (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Difference between the effective tax rate
Federal income tax at U.S. federal statutory rate	$ 273	$ 201	$ 728	$ 621
Foreign income tax rate differential	(29)	(28)	(94)	(86)
State income tax, net of federal benefit	6	3	17	10
Nondeductible expenses	9	6	33	30
Tax benefit of manufacturing deduction	(14)	(8)	(26)	(14)
Foreign dividends, net of foreign tax credits	33	2	43	9
Tax rate change on temporary differences	(5)		(18)
Other	(21)	(7)	(16)	(18)
Provision for income taxes	$ 252	$ 169	$ 667	$ 552

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