Derivative Instruments (Schedule Of Notional Amounts Of Derivatives Outstanding) (Details) (USD $) In Millions, unless otherwise specified	Apr. 26, 2014	Jul. 27, 2013
Derivative [Line Items]
Notional amount of derivatives	$ 14,673	$ 12,992
Designated as Hedging Instrument | Foreign Currency Derivatives
Derivative [Line Items]
Notional amount of derivatives	432	1,885
Designated as Hedging Instrument | Interest Rate Derivatives
Derivative [Line Items]
Notional amount of derivatives	10,400	5,250
Designated as Hedging Instrument | Net Investment Hedging
Derivative [Line Items]
Notional amount of derivatives	328	662
Designated as Hedging Instrument | Equity [Member]
Derivative [Line Items]
Notional amount of derivatives	238	1,098
Derivatives Not Designated As Hedging Instruments | Foreign Currency Derivatives
Derivative [Line Items]
Notional amount of derivatives	2,864	3,739
Derivatives Not Designated As Hedging Instruments | Total Return Swap [Member]
Derivative [Line Items]
Notional amount of derivatives	$ 411	$ 358