Derivative Instruments (Effect Of Derivative Instruments Not Designated As Hedges On Consolidated Statement Of Operations Summary) (Details) - Derivatives not designated as hedging instruments: - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Oct. 29, 2016 |
Oct. 24, 2015 |
|
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| GAINS (LOSSES) FOR THE PERIOD | $ (18) | $ (2) |
| Foreign currency derivatives | Other income (loss), net | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| GAINS (LOSSES) FOR THE PERIOD | (16) | 4 |
| Total return swaps—deferred compensation | Operating expenses | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| GAINS (LOSSES) FOR THE PERIOD | (3) | (16) |
| Equity derivatives/warrants | Other income (loss), net | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| GAINS (LOSSES) FOR THE PERIOD | $ 1 | $ 10 |