Accumulated Other Comprehensive Income (Components Of Accumulated Other Comprehensive Income (Loss)) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jan. 27, 2013		Jan. 29, 2012	Jan. 27, 2013		Jan. 29, 2012	Jul. 29, 2012
Accumulated Other Comprehensive Income [Abstract]
Total comprehensive income	$ 232		$ 182	$ 506		$ 406
Foreign currency translation adjustments, net of tax	295	[1]		295	[1]		261	[1]
Cash-flow hedges, net of tax	(7)	[2]		(7)	[2]		(10)	[2]
Net actuarial loss, net of tax	(993)	[3]		(993)	[3]		(1,034)	[3]
Prior service credit, net of tax	5	[3]		5	[3]		7	[3]
Total Accumulated other comprehensive loss	(700)			(700)			(776)
Foreign currency translation tax expense	16			16			12
Cash flow hedges tax benefit	4			4			6
Unamortized pension and postretirement, tax benefit	$ 560			$ 560			$ 581

[1] Included a tax expense of $16 as of January 27, 2013, and $12 as of July 29, 2012. The amount related to noncontrolling interests was not material.

[2] Included a tax benefit of $4 as of January 27, 2013, and $6 as of July 29, 2012.

[3] Included a tax benefit of $560 as of January 27, 2013, and $581 as of July 29, 2012.