Employee Benefit Plans - Additional Information (Details) $ in Billions	3 Months Ended
Oct. 26, 2019 USD ($) period stock_incentive_plan shares	Oct. 27, 2018 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 \| $	$ 3.1
Expected period of recognition of compensation cost	2 years 9 months 18 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%
ESPP shares purchased during the period (in shares)	0	0
Number of shares reserved for issuance (in shares)	159,000,000
2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares)	694,000,000
PRSU allocation between Financial operating goals and TSR	50.00%
Award requisite service period	3 years
2005 Plan \| Stock awards subsequent to November 12, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in shares available for issuance pursuant to November 12, 2009 amendment (in shares)	1.5
2005 Plan \| PRSU based on financial performance metrics \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation award vesting rights, percentage	0.00%
2005 Plan \| PRSU based on financial performance metrics \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation award vesting rights, percentage	150.00%

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PRSU allocation between Financial operating goals and TSR (in percentage)

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Aggregate number of common shares reserved for future issuance.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Discount rate from fair value on purchase date that participants pay for shares.

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Number of shares issued under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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