Leases - Operating Lease Assets (Details) - USD ($) $ in Millions	Jan. 23, 2021	Jul. 25, 2020
Lessor, Lease, Description [Line Items]
Operating lease assets	$ 11,066	$ 11,014
Accumulated depreciation	(8,680)	(8,561)
Total	2,386	2,453
Operating lease assets
Lessor, Lease, Description [Line Items]
Operating lease assets	343	337
Accumulated depreciation	(201)	(198)
Total	$ 142	$ 139

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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