Financial Instruments (Schedule Of The Fair Value Of Derivative Instruments) (Details) (USD $) In Millions, unless otherwise specified	May 03, 2015	Aug. 03, 2014
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 30	$ 15
Liability Derivatives	27	23
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	2	12
Liability Derivatives	11	1
Designated as Hedging Instrument [Member] | Foreign Exchange Forward Contracts [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	2	1
Designated as Hedging Instrument [Member] | Foreign Exchange Forward Contracts [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	1	1
Designated as Hedging Instrument [Member] | Interest Rate Contract [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	0	11
Designated as Hedging Instrument [Member] | Interest Rate Contract [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	10	0
Derivatives Not Designated As Hedges [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	28	3
Liability Derivatives	16	22
Derivatives Not Designated As Hedges [Member] | Foreign Exchange Forward Contracts [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	3	1
Derivatives Not Designated As Hedges [Member] | Foreign Exchange Forward Contracts [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	7	2
Derivatives Not Designated As Hedges [Member] | Commodity Derivative Contracts [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	2	2
Derivatives Not Designated As Hedges [Member] | Commodity Derivative Contracts [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	9	10
Derivatives Not Designated As Hedges [Member] | Commodity Derivative Contracts [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	0	1
Derivatives Not Designated As Hedges [Member] | Currency Swap [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	23	0
Derivatives Not Designated As Hedges [Member] | Currency Swap [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	0	1
Derivatives Not Designated As Hedges [Member] | Currency Swap [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	0	5
Derivatives Not Designated As Hedges [Member] | Deferred Compensation Derivative Contracts [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	$ 0	$ 3