Stock-Based Compensation (Schedule Of Stock Option Activity) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Jul. 29, 2012
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Beginning of year, Options	8,706
Granted, Options	0
Exercised, Options	(4,370)
Terminated, Options	(82)
End of year, Options	4,254
Exercisable at end of period, Options	4,254
Beginning of period, Weighted-Average Exercise Price	$ 26.23
Granted, Weighted-Average Exercise Price	$ 0.00
Exercised, Weighted-Average Exercise Price	$ 25.75
Terminated, Weighted-Average Exercise Price	$ 26.40
End of period, Weighted-Average Exercise Price	$ 26.73
Exercisable at end of period, Weighted-Average Exercise Price	$ 26.73
Outstanding at end of period, Weighted-Average Remaining Contractual Life (In years)	1.7
Exercisable at end of period, Weighted-Average Remaining Contractual Life (In years)	1.7
Outstanding at end of period, Aggregate Intrinsic Value	$ 27
Exercisable at end of period, Aggregate Intrinsic Value	$ 27