Comprehensive Income (Components Of Accumulated Other Comprehensive Income (Loss)) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Apr. 29, 2012		May 01, 2011	Apr. 29, 2012		May 01, 2011	Jul. 31, 2011
Comprehensive Income [Abstract]
Total comprehensive income	$ 175		$ 348	$ 581		$ 1,007
Foreign currency translation adjustments, net of tax	288	[1]		288	[1]		396	[1]
Cash-flow hedges, net of tax	(13)	[2]		(13)	[2]		(20)	[2]
Net actuarial loss, net of tax	(769)	[3]		(769)	[3]		(809)	[3]
Prior service credit, net of tax	9	[3]		9	[3]		6	[3]
Total Accumulated other comprehensive loss	(485)			(485)			(427)
Foreign currency translation tax expense	16			16			4
Cash flow hedges tax benefit	9			9			11
Unamortized pension and postretirement benefits, tax benefit	$ 435			$ 435			$ 459

[1] (1)Includes a tax expense of $16 as of April 29, 2012, and $4 as of July 31, 2011. The amount related to noncontrolling interests was not material.

[2] (2)Includes a tax benefit of $9 as of April 29, 2012, and $11 as of July 31, 2011.

[3] (3)Includes a tax benefit of $435 as of April 29, 2012, and $459 as of July 31, 2011.