Financial Instruments (Derivatives Not Designated As Hedges) (Details) - USD ($) $ in Millions	3 Months Ended
	Oct. 27, 2019	Oct. 28, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Gain) or Loss Recognized in Earnings on Derivatives	$ (3)	$ 4
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	(2)	0
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	4	(1)
Deferred Compensation Derivative Contracts [Member] | General and Administrative Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Gain) or Loss Recognized in Earnings on Derivatives	$ 1	$ (3)