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. 28, 2019	Jul. 29, 2018
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Defined Benefit Plan, Plan Assets, Amount	$ 2,154	$ 2,183
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	162	137
Defined Benefit Plan, Plan Assets, Contributions by Employer	5	5
Defined Benefit Plan, Plan Assets, Benefits Paid	(141)	(155)
Defined Benefit Plan, Plan Assets, Payment for Settlement	(20)	0
Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss)	(7)	(16)
Defined Benefit Plan, Plan Assets, Amount	$ 2,153	$ 2,154