Financial Instruments (Schedule Of Changes In Cash Flow Hedges In Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Apr. 28, 2019	Apr. 29, 2018	Apr. 28, 2019	Apr. 29, 2018
Derivative Instruments, Gain (Loss) [Line Items]
OCI before tax accumulated derivative gain (loss) beginning of period	$ (8)	$ (22)	$ (8)	$ (34)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	2	11	1	22
OCI before tax accumulated derivative gain (loss) end of period	(7)	(10)	(7)	(10)
Foreign Exchange Forward Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	2	6	1	7
Foreign Exchange Forward Contracts [Member] | Cost Of Products Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(1)	0	(1)	0
Foreign Exchange Forward Contracts [Member] | Other Expenses/Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(1)	0	(1)	0
Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	0	5	0	15
Interest Rate Contract [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ 1	$ 1	$ 2	$ 2