Commitments and Contingencies - Schedule of Financing Guarantees Outstanding (Details) - USD ($) $ in Millions	Jul. 25, 2020	Jul. 27, 2019
Loss Contingencies [Line Items]
Maximum potential future payments relating to financing guarantees:	$ 207	$ 218
Deferred revenue associated with financing guarantees:	(28)	(77)
Total	179	141
Channel partner
Loss Contingencies [Line Items]
Maximum potential future payments relating to financing guarantees:	198	197
Deferred revenue associated with financing guarantees:	(19)	(62)
End user
Loss Contingencies [Line Items]
Maximum potential future payments relating to financing guarantees:	9	21
Deferred revenue associated with financing guarantees:	$ (9)	$ (15)