Financial Instruments (Schedule Of Changes In Cash Flow Hedges In Other Comprehensive Income (Loss)) (Details) (USD $) In Millions, unless otherwise specified							3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended
	Jan. 27, 2013	Oct. 28, 2012	Jul. 29, 2012	Jan. 29, 2012	Oct. 30, 2011	Jul. 31, 2011	Jan. 27, 2013 Foreign Exchange Forward Contracts [Member]	Jan. 29, 2012 Foreign Exchange Forward Contracts [Member]	Jan. 27, 2013 Foreign Exchange Forward Contracts [Member]	Jan. 29, 2012 Foreign Exchange Forward Contracts [Member]	Jan. 27, 2013 Foreign Exchange Forward Contracts [Member] Cost Of Products Sold [Member]	Jan. 29, 2012 Foreign Exchange Forward Contracts [Member] Cost Of Products Sold [Member]	Jan. 27, 2013 Foreign Exchange Forward Contracts [Member] Cost Of Products Sold [Member]	Jan. 29, 2012 Foreign Exchange Forward Contracts [Member] Cost Of Products Sold [Member]	Jan. 27, 2013 Foreign Exchange Forward Contracts [Member] Other Expenses/Income [Member]	Jan. 29, 2012 Foreign Exchange Forward Contracts [Member] Other Expenses/Income [Member]	Jan. 27, 2013 Cross Currency Interest Rate Contract [Member]	Jan. 29, 2012 Cross Currency Interest Rate Contract [Member]	Jan. 27, 2013 Interest Rate Swap [Member]	Jan. 29, 2012 Interest Rate Swap [Member]	Jan. 27, 2013 Interest Rate Swap [Member]	Jan. 29, 2012 Interest Rate Swap [Member]	Jan. 27, 2013 Interest Rate Swap [Member] Interest Expense [Member]	Jan. 29, 2012 Interest Rate Swap [Member] Interest Expense [Member]	Jan. 27, 2013 Interest Rate Swap [Member] Interest Expense [Member]	Jan. 29, 2012 Interest Rate Swap [Member] Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
OCI derivative gain/(loss) at beginning of year	$ (11)	$ (16)	$ (16)	$ (19)	$ (22)	$ (31)
Derivative instruments gain (loss) recognized in OCI							(1)	(2)	(1)	5							0	(1)	5	0	5	0
Derivative instrument gain (loss) reclassified											0	5	(1)	6	0	(1)							1	1	2	2
OCI derivative gain/(loss) at end of year	$ (11)	$ (16)	$ (16)	$ (19)	$ (22)	$ (31)