Commitments and Contingencies - Schedule of Financing Guarantees Outstanding (Details) - USD ($) $ in Millions	Oct. 26, 2019	Jul. 27, 2019
Loss Contingencies [Line Items]
Maximum potential future payments relating to financing guarantees:	$ 163	$ 218
Deferred revenue associated with financing guarantees:	(76)	(77)
Maximum potential future payments relating to financing guarantees, net of associated deferred revenue	87	141
Channel partner
Loss Contingencies [Line Items]
Maximum potential future payments relating to financing guarantees:	148	197
Deferred revenue associated with financing guarantees:	(61)	(62)
End user
Loss Contingencies [Line Items]
Maximum potential future payments relating to financing guarantees:	15	21
Deferred revenue associated with financing guarantees:	$ (15)	$ (15)