Employee Benefit Plans - Summary of Restricted Stock and Stock Unit Activity (Details) - Restricted Stock/Stock Units - USD ($) $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended	12 Months Ended
	May 01, 2021	Jul. 25, 2020
Restricted Stock/ Stock Units
Beginning balance (in shares)	96	100
Granted and assumed (in shares)	35	49
Vested (in shares)	(27)	(44)
Canceled/forfeited/other (in shares)	(11)	(9)
Ending balance (in shares)	93	96
Weighted-Average Grant Date Fair Value per Share
Beginning balance (in dollars per share)	$ 42.03	$ 38.66
Granted and assumed (in dollars per share)	38.39	42.61
Vested (in dollars per share)	39.65	35.20
Canceled/forfeited/other (in dollars per share)	42.14	40.45
Ending balance (in dollars per share)	$ 41.34	$ 42.03
Aggregate Fair  Value
Vested	$ 1,188	$ 2,045