Financial Instruments (Derivatives Not Designated As Hedges) (Details) (USD $) In Millions	12 Months Ended
	Jul. 31, 2011	Aug. 01, 2010
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	$ (81)	$ (11)
Foreign Exchange Contracts [Member] | Other Expenses/Income [Member]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives		(8)
Foreign Exchange Contracts [Member] | Cost of Products Sold [Member]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	(1)
Cross-currency Swap Contracts [Member] | Other Expenses/Income [Member]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	(88)	(12)
Commodity Derivative Contracts [Member] | Cost of Products Sold [Member]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	7
Equity Contracts [Member] | Administrative Expense [Member]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	$ 1	$ 9