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, unless otherwise specified	3 Months Ended		9 Months Ended
	Apr. 25, 2015	Apr. 26, 2014	Apr. 25, 2015	Apr. 26, 2014
Derivative Instruments, Gain (Loss) [Line Items]
GAINS (LOSSES) FOR THE THREE MONTHS ENDED	$ (27)	$ 49	$ (132)	$ 82
Foreign currency derivatives | Other income (loss), net
Derivative Instruments, Gain (Loss) [Line Items]
GAINS (LOSSES) FOR THE THREE MONTHS ENDED	(56)	36	(165)	16
Total return swaps—deferred compensation | Operating expenses
Derivative Instruments, Gain (Loss) [Line Items]
GAINS (LOSSES) FOR THE THREE MONTHS ENDED	23	4	23	33
Equity derivatives | Other income (loss), net
Derivative Instruments, Gain (Loss) [Line Items]
GAINS (LOSSES) FOR THE THREE MONTHS ENDED	$ 6	$ 9	$ 10	$ 33