Derivative Instruments - Effect of Derivative Instruments Not Designated as Hedges on Consolidated Statements of Operations (Details) - Derivatives not designated as hedging instruments: - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jan. 23, 2021	Jan. 25, 2020	Jan. 23, 2021	Jan. 25, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses)	$ 118	$ 42	$ 160	$ 37
Foreign currency derivatives | Other income (loss), net
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses)	33	(2)	47	(9)
Total return swaps—deferred compensation | Operating expenses and other
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses)	76	41	99	41
Equity derivatives | Other income (loss), net
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses)	$ 9	$ 3	$ 14	$ 5