Employee Benefit Plans - Additional Information (Details) $ in Billions	3 Months Ended
Oct. 24, 2020 USD ($) period stock_incentive_plan shares	Oct. 26, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock incentive plans (stock incentive plan) \| stock_incentive_plan	1
Total compensation cost related to unvested share-based awards \| $	$ 3.6
Expected period of recognition of compensation cost	2 years 10 months 24 days
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares)	721,400,000
Consecutive offering period	24 months
Number of purchase periods \| period	4
Purchase period	6 months
ESPP discount percentage from market price, beginning of purchase period	15.00%
Shares issued under employee purchase plan, shares (in shares)	0	0
Number of shares reserved for issuance (in shares)	141,000,000
2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares)	694,000,000
2005 Plan \| Stock awards subsequent to November 12, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares)	175,000,000
Reduction in shares available for issuance pursuant to November 12, 2009 amendment (in shares)	1.5

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