Stock-based Compensation (Schedule Of Stock Option Activity) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended
	Oct. 27, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Beginning of year, Options	1,101
Granted, Options	0
Exercised, Options	(133)
Terminated, Options	0
End of year, Options	968
Exercisable at end of period, Options	968
Beginning of period, Weighted-Average Exercise Price	$ 27.25
Granted, Weighted-Average Exercise Price	$ 0.00
Exercised, Weighted-Average Exercise Price	$ 26.75
Terminated, Weighted-Average Exercise Price	$ 0.00
End of period, Weighted-Average Exercise Price	$ 27.33
Exercisable at end of period, Weighted-Average Exercise Price	$ 27.33
Outstanding at end of period, Weighted-Average Remaining Contractual Life (In years)	1 year 1 month
Exercisable at end of period, Weighted-Average Remaining Contractual Life (In years)	1 year 1 month
Outstanding at end of period, Aggregate Intrinsic Value	$ 15
Exercisable at end of period, Aggregate Intrinsic Value	$ 15