Pension And Postretirement Benefits (Schedule of Change In Fair Value Of Pension Assets) (Details) - Pension Plan, Defined Benefit [Member] - USD ($) $ in Millions	12 Months Ended
	Jul. 29, 2018	Jul. 30, 2017
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Defined Benefit Plan, Fair Value of Plan Assets	$ 2,183	$ 2,111
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	137	208
Defined Benefit Plan, Plan Assets, Contributions by Employer	5	5
Defined Benefit Plan, Plan Assets, Benefits Paid	(155)	(154)
Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss)	(16)	13
Defined Benefit Plan, Fair Value of Plan Assets	$ 2,154	$ 2,183