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
	Aug. 02, 2020	Jul. 28, 2019
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Defined Benefit Plan, Plan Assets, Amount	$ 2,153	$ 2,154
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	230	162
Defined Benefit Plan, Plan Assets, Contributions by Employer	(2)	(5)
Defined Benefit Plan, Plan Assets, Benefits Paid	(135)	(141)
Defined Benefit Plan, Plan Assets, Payment for Settlement	(41)	(20)
Defined Benefit Plan, Plan Assets, Divestiture	(86)	0
Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss)	(3)	(7)
Defined Benefit Plan, Plan Assets, Amount	$ 2,120	$ 2,153