Pension And Postretirement Benefits (Schedule Of Assumed Health Care Cost Trend Rates) (Details) - Other Postretirement Benefit Plan, Defined Benefit [Member]	12 Months Ended
	Jul. 29, 2018	Jul. 30, 2017
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year	6.75%	7.25%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	4.50%	4.50%
Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate	2023	2023