Stock-based Compensation (Schedule Of Stock Option Activity) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Jul. 28, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Beginning of year, Options	4,254
Granted, Options	0
Exercised, Options	(3,146)
Terminated, Options	(7)
End of year, Options	1,101
Exercisable at end of period, Options	1,101
Beginning of period, Weighted-Average Exercise Price	$ 26.73
Granted, Weighted-Average Exercise Price
Exercised, Weighted-Average Exercise Price	$ 26.54
Terminated, Weighted-Average Exercise Price	$ 26.36
End of period, Weighted-Average Exercise Price	$ 27.25
Exercisable at end of period, Weighted-Average Exercise Price	$ 27.25
Outstanding at end of period, Weighted-Average Remaining Contractual Life (In years)	1 year 2 months
Exercisable at end of period, Weighted-Average Remaining Contractual Life (In years)	1 year 2 months
Outstanding at end of period, Aggregate Intrinsic Value	$ 22
Exercisable at end of period, Aggregate Intrinsic Value	$ 22