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	12 Months Ended
	Jul. 29, 2017	Jul. 30, 2016	Jul. 25, 2015
Derivative Instruments, Gain (Loss) [Line Items]
GAINS (LOSSES) FOR THE YEARS ENDED	$ 82	$ 1	$ (127)
Foreign currency derivatives | Other income (loss), net
Derivative Instruments, Gain (Loss) [Line Items]
GAINS (LOSSES) FOR THE YEARS ENDED	13	(19)	(173)
Total return swaps—deferred compensation | Operating expenses
Derivative Instruments, Gain (Loss) [Line Items]
GAINS (LOSSES) FOR THE YEARS ENDED	58	7	19
Equity derivatives | Other income (loss), net
Derivative Instruments, Gain (Loss) [Line Items]
GAINS (LOSSES) FOR THE YEARS ENDED	$ 11	$ 13	$ 27