Commitments and Contingencies (Schedule of Financing Guarantees Outstanding) (Details) - USD ($) $ in Millions	Oct. 24, 2015	Jul. 25, 2015
Loss Contingencies [Line Items]
Maximum potential future payments relating to financing guarantees:	$ 374	$ 417
Deferred revenue associated with financing guarantees:	(196)	(234)
Maximum potential future payments relating to financing guarantees, net of associated deferred revenue	178	183
Channel partner
Loss Contingencies [Line Items]
Maximum potential future payments relating to financing guarantees:	250	288
Deferred revenue associated with financing guarantees:	(96)	(127)
End user
Loss Contingencies [Line Items]
Maximum potential future payments relating to financing guarantees:	124	129
Deferred revenue associated with financing guarantees:	$ (100)	$ (107)