Employee Benefit Plans - Summary of Restricted Stock and Stock Unit Activity (Details) - Restricted Stock Units - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	12 Months Ended
	Oct. 30, 2021	Jul. 31, 2021
Restricted Stock/ Stock Units
Beginning balance (in shares)	94	96
Granted and assumed (in shares)	8	51
Vested (in shares)	(8)	(39)
Canceled/forfeited/other (in shares)	(3)	(14)
Ending balance (in shares)	91	94
Weighted-Average Grant Date Fair Value per Share
Beginning balance (in dollars per share)	$ 42.93	$ 42.03
Granted and assumed (in dollars per share)	54.37	41.89
Vested (in dollars per share)	41.84	39.63
Canceled/forfeited/other (in dollars per share)	43.51	42.13
Ending balance (in dollars per share)	$ 43.99	$ 42.93
Aggregate Fair  Value
Vested	$ 393	$ 1,813