Pension And Postretirement Benefits (Schedule Of Pension Plan Assets By Category) (Details) (Pension Plan, Defined Benefit [Member], USD $) In Millions, unless otherwise specified	Aug. 03, 2014	Jul. 28, 2013	Jul. 29, 2012
Defined Benefit Plan, Fair Value of Plan Assets	$ 2,364	$ 2,275	$ 2,118
Short-term Investments [Member]
Defined Benefit Plan, Fair Value of Plan Assets	60	78
US Government and Government Agencies and Authorities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	62	41
Foreign Government Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	46	37
Municipal Bonds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	84	73
Asset-backed Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	13	15
Real Estate [Member]
Defined Benefit Plan, Fair Value of Plan Assets	117	107
Hedge Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	181	147
Other Items To Reconcile To Fair Value Of Plan Assets [Member]
Defined Benefit Plan, Fair Value of Plan Assets	(16)	(4)
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan, Fair Value of Plan Assets	738	801
Fair Value, Inputs, Level 1 [Member] | Short-term Investments [Member]
Defined Benefit Plan, Fair Value of Plan Assets	23	36
Fair Value, Inputs, Level 1 [Member] | US Government and Government Agencies and Authorities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Foreign Government Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Municipal Bonds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Asset-backed Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | Real Estate [Member]
Defined Benefit Plan, Fair Value of Plan Assets	5	6
Fair Value, Inputs, Level 1 [Member] | Hedge Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan, Fair Value of Plan Assets	1,568	1,430
Fair Value, Inputs, Level 2 [Member] | Short-term Investments [Member]
Defined Benefit Plan, Fair Value of Plan Assets	37	42
Fair Value, Inputs, Level 2 [Member] | US Government and Government Agencies and Authorities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	62	41
Fair Value, Inputs, Level 2 [Member] | Foreign Government Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	46	37
Fair Value, Inputs, Level 2 [Member] | Municipal Bonds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	84	73
Fair Value, Inputs, Level 2 [Member] | Asset-backed Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	13	15
Fair Value, Inputs, Level 2 [Member] | Real Estate [Member]
Defined Benefit Plan, Fair Value of Plan Assets	92	83
Fair Value, Inputs, Level 2 [Member] | Hedge Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	127	117
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Fair Value of Plan Assets	74	48	35
Fair Value, Inputs, Level 3 [Member] | Short-term Investments [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | US Government and Government Agencies and Authorities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Foreign Government Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Municipal Bonds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Asset-backed Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Real Estate [Member]
Defined Benefit Plan, Fair Value of Plan Assets	20	18	35
Fair Value, Inputs, Level 3 [Member] | Hedge Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	54	30	0
Total Before Other Items [Member]
Defined Benefit Plan, Fair Value of Plan Assets	2,380	2,279
Equity Funds [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	426	393
Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Equity Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	426	393
Equity Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fixed Income Funds [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	3	29
Fixed Income Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fixed Income Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	3	29
Fixed Income Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Blended Funds [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	95	88
Blended Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Blended Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	95	88
Blended Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Commingled Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
UNITED STATES | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	378	401
UNITED STATES | Domestic Corporate Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	469	420
UNITED STATES | Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	378	401
UNITED STATES | Fair Value, Inputs, Level 1 [Member] | Domestic Corporate Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
UNITED STATES | Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
UNITED STATES | Fair Value, Inputs, Level 2 [Member] | Domestic Corporate Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	469	420
UNITED STATES | Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
UNITED STATES | Fair Value, Inputs, Level 3 [Member] | Domestic Corporate Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Non-U.S. [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	332	358
Non-U.S. [Member] | Domestic Corporate Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	114	92
Non-U.S. [Member] | Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	332	358
Non-U.S. [Member] | Fair Value, Inputs, Level 1 [Member] | Domestic Corporate Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Non-U.S. [Member] | Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Non-U.S. [Member] | Fair Value, Inputs, Level 2 [Member] | Domestic Corporate Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	114	92
Non-U.S. [Member] | Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Non-U.S. [Member] | Fair Value, Inputs, Level 3 [Member] | Domestic Corporate Debt Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets	$ 0	$ 0