Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements (Financial Assets Measured At Fair Value On A Recurring and Nonrecurring Basis) (Details)

v3.21.2
Fair Value Measurements (Financial Assets Measured At Fair Value On A Recurring and Nonrecurring Basis) (Details) - USD ($)
$ in Millions
Jul. 31, 2021
Aug. 01, 2020
Marketable equity and debt securities $ 46 $ 143
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]    
Marketable equity and debt securities 39 32
Significant Observable Inputs (Level 2) [Member]    
Marketable equity and debt securities 7 111
Significant Unobservable Inputs (Level 3) [Member]    
Marketable equity and debt securities $ 0 $ 0