Pension And Postretirement Benefits Pension And Postretirement Benefits (Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost) (Details) (Pension Plans, Defined Benefit [Member])	12 Months Ended
	Jul. 29, 2012	Jul. 31, 2011	Aug. 01, 2010
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.41%	5.46%	6.00%
Expected return on plan assets	7.90%	8.15%	8.13%
Rate of compensation increase	3.31%	3.29%	3.29%