Financial Instruments (Schedule Of Changes In Cash Flow Hedges In Other Comprehensive Income (Loss)) (Details) (USD $) In Millions, unless otherwise specified							3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Apr. 28, 2013	Jan. 27, 2013	Jul. 29, 2012	Apr. 29, 2012	Jan. 29, 2012	Jul. 31, 2011	Apr. 28, 2013 Foreign Exchange Forward Contracts [Member]	Apr. 29, 2012 Foreign Exchange Forward Contracts [Member]	Apr. 28, 2013 Foreign Exchange Forward Contracts [Member]	Apr. 29, 2012 Foreign Exchange Forward Contracts [Member]	Apr. 28, 2013 Foreign Exchange Forward Contracts [Member] Cost Of Products Sold [Member]	Apr. 29, 2012 Foreign Exchange Forward Contracts [Member] Cost Of Products Sold [Member]	Apr. 28, 2013 Foreign Exchange Forward Contracts [Member] Cost Of Products Sold [Member]	Apr. 29, 2012 Foreign Exchange Forward Contracts [Member] Cost Of Products Sold [Member]	Apr. 28, 2013 Interest Rate Swap [Member]	Apr. 29, 2012 Interest Rate Swap [Member]	Apr. 28, 2013 Interest Rate Swap [Member]	Apr. 29, 2012 Interest Rate Swap [Member]	Apr. 28, 2013 Interest Rate Swap [Member] Interest Expense [Member]	Apr. 29, 2012 Interest Rate Swap [Member] Interest Expense [Member]	Apr. 28, 2013 Interest Rate Swap [Member] Interest Expense [Member]	Apr. 29, 2012 Interest Rate Swap [Member] Interest Expense [Member]	Apr. 28, 2013 Currency Swap [Member]	Apr. 29, 2012 Currency Swap [Member]	Apr. 28, 2013 Currency Swap [Member]	Apr. 29, 2012 Currency Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
OCI derivative gain/(loss) at beginning of year	$ (16)	$ (11)	$ (16)	$ (22)	$ (19)	$ (31)
Derivative instruments gain (loss) recognized in OCI							0	2	(1)	7					(6)	0	(1)	0					1	1	1	0
Derivative instrument (gain) loss reclassified											(1)	(6)	(2)	0					1	0	3	2
OCI derivative gain/(loss) at end of year	$ (16)	$ (11)	$ (16)	$ (22)	$ (19)	$ (31)