Pension And Postretirement Benefits (Schedule Of Amounts Recognized In The Consolidated Balance Sheets) (Details) (USD $) In Millions	Jul. 31, 2011	Aug. 01, 2010
Pension [Member]
Accrued liabilities	$ (10)	$ (8)
Other liabilities	(319)	(500)
Net amount recognized	(329)	(508)
Net actuarial loss	1,179	1,263
Prior service credit	(3)	(1)
Total	1,176	1,262
Postretirement [Member]
Accrued liabilities	(30)	(30)
Other liabilities	(344)	(332)
Net amount recognized	(374)	(362)
Net actuarial loss	95	87
Prior service credit	(9)	(10)
Total	$ 86	$ 77