Restructuring Charges (Schedule Of Restructuring Activity And Related Reserves) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jan. 29, 2012
Restructuring Cost and Reserve [Line Items]
Accrued Balance at beginning of period	$ 39
Charges	5
Cash Payments	(17)
Foreign Currency Translation Adjustment	(1)
Accrued Balance at end of period	25
Severance Pay And Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Accrued Balance at beginning of period	35
Charges	2
Cash Payments	(15)
Foreign Currency Translation Adjustment	(1)
Accrued Balance at end of period	21
Asset Impairment/Accelerated Depreciation [Member]
Restructuring Cost and Reserve [Line Items]
Charges	1
Other Exit Costs [Member]
Restructuring Cost and Reserve [Line Items]
Accrued Balance at beginning of period	4
Charges	2
Cash Payments	(2)
Accrued Balance at end of period	$ 4