Leases - Operating Lease Assets (Details) - USD ($) $ in Millions	Jan. 25, 2020	Jul. 27, 2019
Lessor, Lease, Description [Line Items]
Operating lease assets	$ 11,337	$ 12,039
Accumulated depreciation	(8,716)	(9,250)
Total	2,621	2,789
Property Subject to or Available for Operating Lease, Net [Abstract]
Operating lease assets		485
Accumulated depreciation		(306)
Operating lease assets, net		$ 179
Operating lease assets
Lessor, Lease, Description [Line Items]
Operating lease assets	411
Accumulated depreciation	(247)
Total	$ 164

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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The amount of accumulated depreciation, by major property class, recorded on property subject to or available for lease as of the balance sheet date.

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