Derivative Instruments (Schedule Of Notional Amounts Of Derivatives Outstanding) (Details) - USD ($) $ in Millions	Jul. 25, 2015	Jul. 26, 2014
Derivative [Line Items]
Derivatives	$ 15,278	$ 15,557
Derivatives designated as hedging instruments: | Foreign currency derivatives
Derivative [Line Items]
Derivatives	1,201	1,618
Derivatives designated as hedging instruments: | Interest rate derivatives
Derivative [Line Items]
Derivatives	11,400	10,400
Derivatives designated as hedging instruments: | Net investment hedging instruments
Derivative [Line Items]
Derivatives	192	345
Derivatives designated as hedging instruments: | Equity derivatives
Derivative [Line Items]
Derivatives	0	238
Derivatives not designated as hedging instruments: | Foreign currency derivatives
Derivative [Line Items]
Derivatives	2,023	2,528
Derivatives not designated as hedging instruments: | Total return swaps—deferred compensation
Derivative [Line Items]
Derivatives	$ 462	$ 428