Derivative Instruments (Schedule Of Notional Amounts Of Derivatives Outstanding) (Details) (USD $) In Millions, unless otherwise specified	Jul. 26, 2014	Jul. 27, 2013
Derivative [Line Items]
Derivatives	$ 15,557	$ 12,992
Derivatives designated as hedging instruments: | Foreign currency derivatives
Derivative [Line Items]
Derivatives	1,618	1,885
Derivatives designated as hedging instruments: | Interest rate derivatives
Derivative [Line Items]
Derivatives	10,400	5,250
Derivatives designated as hedging instruments: | Net investment hedging instruments
Derivative [Line Items]
Derivatives	345	662
Derivatives designated as hedging instruments: | Equity derivatives
Derivative [Line Items]
Derivatives	238	1,098
Derivatives not designated as hedging instruments: | Foreign currency derivatives
Derivative [Line Items]
Derivatives	2,528	3,739
Derivatives not designated as hedging instruments: | Total return swaps—deferred compensation
Derivative [Line Items]
Derivatives	$ 428	$ 358