Pension And Postretirement Benefits (Amounts Recognized in Consolidated Balance Sheets) (Details) (USD $) In Millions, unless otherwise specified	Aug. 03, 2014	Jul. 28, 2013
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan, Assets for Plan Benefits, Noncurrent	$ 7	$ 0
Pension and Other Postretirement Defined Benefit Plans, Current Liabilities	(12)	(13)
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	(170)	(190)
Disposal Group, Including Discontinued Operation, Pension Plan Benefit Obligation	0	(11)
Defined Benefit Plan, Amounts Recognized in Balance Sheet	(175)	(214)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	1,019	1,068
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax	(2)	(2)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax	1,017	1,066
Other Postretirement Benefit Plan, Defined Benefit [Member]
Defined Benefit Plan, Assets for Plan Benefits, Noncurrent	0	0
Pension and Other Postretirement Defined Benefit Plans, Current Liabilities	(29)	(29)
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	(359)	(361)
Disposal Group, Including Discontinued Operation, Pension Plan Benefit Obligation	0	0
Defined Benefit Plan, Amounts Recognized in Balance Sheet	(388)	(390)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	96	104
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax	(5)	(6)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax	$ 91	$ 98