Derivative Instruments - Schedule of Notional Amounts of Derivatives Outstanding (Details) - USD ($) $ in Millions	Jul. 25, 2020	Jul. 27, 2019
Derivative [Line Items]
Derivative, notional amount	$ 7,395	$ 8,754
Derivatives designated as hedging instruments | Foreign currency derivatives
Derivative [Line Items]
Derivative, notional amount	743	663
Derivatives designated as hedging instruments | Interest rate derivatives
Derivative [Line Items]
Derivative, notional amount	2,500	4,500
Derivatives designated as hedging instruments | Net investment hedging instruments
Derivative [Line Items]
Derivative, notional amount	331	309
Derivatives not designated as hedging instruments | Foreign currency derivatives
Derivative [Line Items]
Derivative, notional amount	3,241	2,708
Derivatives not designated as hedging instruments | Total return swaps—deferred compensation
Derivative [Line Items]
Derivative, notional amount	$ 580	$ 574