Restructuring Charges (Schedule Of Restructuring Activity And Related Reserves) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Apr. 29, 2012	Jul. 31, 2011	May 01, 2011	Apr. 29, 2012	May 01, 2011
Restructuring Cost and Reserve [Line Items]
Accrued Balance at beginning of period				$ 39
Charges				6
Cash Payments				(23)
Foreign Currency Translation Adjustment				(1)
Accrued Balance at end of period	21	39		21
Restructuring Charges	4	63	0	9	0
Severance Pay And Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Accrued Balance at beginning of period				35
Charges				4
Cash Payments				(20)
Foreign Currency Translation Adjustment				(1)
Accrued Balance at end of period	18			18
Other Exit Costs [Member]
Restructuring Cost and Reserve [Line Items]
Accrued Balance at beginning of period				4
Charges				2
Cash Payments				(3)
Foreign Currency Translation Adjustment				0
Accrued Balance at end of period	3			3
Asset Impairment/Accelerated Depreciation [Member]
Restructuring Cost and Reserve [Line Items]
Charges				1
Contract Termination, Charges Recorded Directly to the Income Statement [Member]
Restructuring Cost and Reserve [Line Items]
Charges				$ 2