Pension And Postretirement Benefits (Schedule Of Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets) (Details) - Pension Plan, Defined Benefit [Member] - USD ($) $ in Millions	Jul. 29, 2018	Jul. 30, 2017
Defined Benefit Plan, Plan with Benefit Obligation in Excess of Plan Assets [Abstract]
Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation	$ 249	$ 2,270
Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation	241	2,232
Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Fair Value of Plan Assets	$ 85	$ 1,995