Fair Value Measurements (Financial Assets Measured At Fair Value On A Recurring and Nonrecurring Basis) (Details) - USD ($) $ in Millions |
Jul. 30, 2022 |
Jul. 31, 2021 |
|---|---|---|
| Marketable equity and debt securities | $ 34 | $ 46 |
| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | ||
| Marketable equity and debt securities | 34 | 39 |
| Significant Observable Inputs (Level 2) [Member] | ||
| Marketable equity and debt securities | 0 | 7 |
| Significant Unobservable Inputs (Level 3) [Member] | ||
| Marketable equity and debt securities | $ 0 | $ 0 |