Restructuring And Other Charges (Schedule Of Activities Related To Restructuring And Other Charges) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
	Apr. 28, 2012	Jul. 30, 2011
Restructuring Cost and Reserve [Line Items]
Beginning balance	$ 262
Charges	225	799
Cash payments	(413)	(449)
Non-cash items	(19)	(88)
Ending balance	55	262
Voluntary Early Retirement Program [Member]
Restructuring Cost and Reserve [Line Items]
Beginning balance	17
Charges		453
Cash payments	(17)	(436)
Ending balance		17
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Beginning balance	234
Charges	195	247
Cash payments	(380)	(13)
Ending balance	49	234
Goodwill And Intangible Assets [Member]
Restructuring Cost and Reserve [Line Items]
Charges		71
Non-cash items		(71)
All Others [Member]
Restructuring Cost and Reserve [Line Items]
Beginning balance	11
Charges	30	28
Cash payments	(16)
Non-cash items	(19)	(17)
Ending balance	$ 6	$ 11