Financing Receivables and Guarantees (Schedule Of Financing Guarantees Outstanding) (Detail) (USD $) In Millions, unless otherwise specified	Jul. 27, 2013	Jul. 28, 2012
Guarantor Obligations [Line Items]
Maximum potential future payments relating to financing guarantees	$ 675	$ 509
Deferred revenue associated with financing guarantees	(416)	(393)
Maximum potential future payments relating to financing guarantees, net of associated deferred revenue	259	116
Channel Partner
Guarantor Obligations [Line Items]
Maximum potential future payments relating to financing guarantees	438	277
Deferred revenue associated with financing guarantees	(225)	(193)
End User
Guarantor Obligations [Line Items]
Maximum potential future payments relating to financing guarantees	237	232
Deferred revenue associated with financing guarantees	$ (191)	$ (200)