Leases - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 24, 2020	Oct. 26, 2019
Leases [Abstract]
Weighted-average remaining lease term (in years)	4 years 2 months 12 days	4 years 2 months 12 days
Weighted-average discount rate	1.30%	1.90%
Sales-type lease terms, on average	4 years
Interest income, lease receivables	$ 21	$ 26
Operating lease income	$ 43	$ 44

No definition available.

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- Definition

Term of lessor's sales-type lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
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- Definition

Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

+ References

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

Amount of interest income from lease receivable of sales-type lease.

+ References

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