Fair Value - Fair Value, Nonrecurring Measurement (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 26, 2019	Oct. 27, 2018
Non-marketable equity securities and equity method investments \| Fair value, measurements, nonrecurring \| Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total gains (losses) for nonrecurring measurements	$ (21)	$ (6)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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