Pension And Postretirement Benefits (Weighted-average Assumptions To Determine Benefit Obligations) (Details)	Jul. 29, 2018	Jul. 30, 2017
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.15%	3.74%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase	3.21%	3.24%
Other Postretirement Benefit Plan, Defined Benefit [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.06%	3.45%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase	3.25%	3.25%