Recent Accounting Pronouncements (Details) - USD ($) $ in Millions	Apr. 25, 2020	Jul. 28, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use asset	$ 930
Operating lease liabilities	$ 998
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use asset		$ 1,200
Operating lease liabilities		$ 1,200