Employee Benefit Plans - Additional Information (Details) $ in Billions	3 Months Ended		9 Months Ended
	Apr. 25, 2020 USD ($) stock_incentive_plan shares	Apr. 27, 2019 shares	Apr. 25, 2020 USD ($) period stock_incentive_plan shares	Apr. 27, 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		1
Total compensation cost related to unvested share-based awards | $	$ 3.4		$ 3.4
Expected period of recognition of compensation cost			2 years 7 months 6 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		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	9,000,000	9,000,000
Number of shares reserved for issuance (in shares)	150,000,000		150,000,000
2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares)	694,000,000		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)	200,000,000		200,000,000
Reduction in shares available for issuance pursuant to November 12, 2009 amendment (in shares)	1.5		1.5