Financial Instruments (Schedule Of The Fair Value Of Derivative Instruments) (Details) (USD $) In Millions, unless otherwise specified	Apr. 27, 2014	Jul. 28, 2013
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 27	$ 32
Liability Derivatives	5	36
Cash Flow Hedging [Member] | Cross-Currency Swap Contracts [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	0	22
Cash Flow Hedging [Member] | Foreign Exchange Forward Contracts [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	1	2
Cash Flow Hedging [Member] | Foreign Exchange Forward Contracts [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	1	2
Cash Flow Hedging [Member] | Interest Rate Contract [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	17	0
Cash Flow Hedging [Member] | Interest Rate Contract [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	0	23
Fair Value Hedging [Member] | Interest Rate Swap [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	0	1
Derivatives Designated As Hedges [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	18	26
Liability Derivatives	1	24
Derivatives Not Designated As Hedges [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	9	6
Liability Derivatives	4	12
Derivatives Not Designated As Hedges [Member] | Commodity Derivative Contracts [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	7	2
Derivatives Not Designated As Hedges [Member] | Commodity Derivative Contracts [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	0	6
Derivatives Not Designated As Hedges [Member] | Cross-Currency Swap Contracts [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	0	1
Derivatives Not Designated As Hedges [Member] | Cross-Currency Swap Contracts [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	3	1
Derivatives Not Designated As Hedges [Member] | Foreign Exchange Forward Contracts [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	2	2
Derivatives Not Designated As Hedges [Member] | Foreign Exchange Forward Contracts [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	1	4
Derivatives Not Designated As Hedges [Member] | Deferred Compensation Derivative Contracts [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 0	$ 2