Financial Instruments (Derivatives Not Designated As Hedges) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Apr. 27, 2014	Apr. 28, 2013	Apr. 27, 2014	Apr. 28, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	$ 2	$ 30	$ 15	$ 16
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)	0	4	(1)
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	1	(12)	1
Cross-Currency Swap Contracts [Member] | Other Expenses/Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	(11)	15	10	(3)
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	11	5	11	4
Deferred Compensation Derivative Contracts [Member] | Administrative Expenses [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	$ 3	$ 9	$ 2	$ 15