Financial Instruments (Derivatives Not Designated As Hedges) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Feb. 01, 2015	Jan. 26, 2014	Feb. 01, 2015	Jan. 26, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	$ 25	$ 31	$ 37	$ 13
Foreign Exchange Forward Contracts [Member] | Cost Of Products Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	(1)	3	0	5
Foreign Exchange Forward Contracts [Member] | Other Expenses Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	0	2	0	(12)
Currency Swap [Member] | Other Expenses Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	38	24	52	21
Commodity Derivative Contracts [Member] | Cost Of Products Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	(13)	2	(18)	0
Deferred Compensation Derivative Contracts [Member] | Administrative Expenses [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	$ 1	$ 0	$ 3	$ (1)