Pension And Postretirement Benefits Pension And Postretirement Benefits (Schedule Of Change In The Fair Value Of Pension Plan Assets) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 29, 2012	Jul. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Fair value at end of year	$ 2,118	$ 2,059
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value at beginning of year	2,059	1,767
Actual return on plan assets	149	266
Employer contributions	71	144
Defined Benefit Plan, Benefits Paid, Plan Assets	(149)	(139)
Settlements	0	(6)
Foreign currency adjustment	(12)	27
Fair value at end of year	$ 2,118	$ 2,059