Stock-based Compensation (Schedule Of Stock Option Activity) (Details) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Oct. 30, 2016 USD ($) $ / shares shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Beginning of year, Options | shares	681
Granted, Options | shares	489
Exercised, Options | shares	0
Terminated, Options | shares	(95)
End of year, Options | shares	1,075
Exercisable at end of period, Options | shares	227
Beginning of period, Weighted-Average Exercise Price | $ / shares	$ 50.21
Granted, Weighted-Average Exercise Price | $ / shares	54.65
Exercised, Weighted-Average Exercise Price | $ / shares	0.00
Terminated, Weighted-Average Exercise Price | $ / shares	52.49
End of period, Weighted-Average Exercise Price | $ / shares	52.02
Exercisable at end of period, Weighted-Average Exercise Price | $ / shares	$ 50.21
Outstanding at end of period, Weighted-Average Remaining Contractual Life (In years)	9 years 4 months
Exercisable at end of period, Weighted-Average Remaining Contractual Life (In years)	8 years 11 months
Outstanding at end of period, Aggregate Intrinsic Value | $	$ 3
Exercisable at end of period, Aggregate Intrinsic Value | $	$ 1