Leases - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jan. 29, 2022	Jan. 23, 2021	Jan. 29, 2022	Jan. 23, 2021	Jul. 31, 2021
Leases [Abstract]
Weighted-average remaining lease term (in years)	4 years 8 months 12 days		4 years 8 months 12 days		5 years 2 months 12 days
Weighted-average discount rate	1.70%		1.70%		1.70%
Sales-type lease terms, on average	4 years		4 years
Interest income, lease receivables	$ 14	$ 19	$ 29	$ 40
Operating lease income	$ 29	$ 40	$ 61	$ 83