Financing Receivables And Guarantees (Schedule Of Financing Guarantees Outstanding) (Detail) (USD $) In Millions, unless otherwise specified	Jan. 25, 2014	Jul. 27, 2013
Financing Guarantee Summary [Line Items]
Maximum potential future payments relating to financing guarantees	$ 705	$ 675
Deferred revenue associated with financing guarantees	(440)	(416)
Maximum potential future payments relating to financing guarantees, net of associated deferred revenue	265	259
Channel Partner
Financing Guarantee Summary [Line Items]
Maximum potential future payments relating to financing guarantees	479	438
Deferred revenue associated with financing guarantees	(251)	(225)
End User
Financing Guarantee Summary [Line Items]
Maximum potential future payments relating to financing guarantees	226	237
Deferred revenue associated with financing guarantees	$ (189)	$ (191)