Stock-based Compensation (Schedule Of Stock Option Activity) (Details) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Jul. 29, 2018 USD ($) $ / shares shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Beginning of year, Options | shares	1,042
Granted, Options | shares	575
Exercised, Options | shares	0
Terminated, Options | shares	(80)
End of year, Options | shares	1,537
Exercisable at end of period, Options | shares	519
Beginning of period, Weighted-Average Exercise Price | $ / shares	$ 52.08
Granted, Weighted-Average Exercise Price | $ / shares	47.19
Exercised, Weighted-Average Exercise Price | $ / shares	0.00
Terminated, Weighted-Average Exercise Price | $ / shares	50.05
End of period, Weighted-Average Exercise Price | $ / shares	50.36
Exercisable at end of period, Weighted-Average Exercise Price | $ / shares	$ 51.40
Outstanding at end of period, Weighted-Average Remaining Contractual Life (In years)	8 years 2 months
Exercisable at end of period, Weighted-Average Remaining Contractual Life (In years)	7 years 6 months
Outstanding at end of period, Aggregate Intrinsic Value | $	$ 0
Exercisable at end of period, Aggregate Intrinsic Value | $	$ 0