Derivative Instruments (Derivatives Recorded At Fair Value) (Details) (USD $) In Millions, unless otherwise specified	Oct. 25, 2014	Jul. 26, 2014
Derivative [Line Items]
DERIVATIVE ASSETS	$ 227	$ 160
DERIVATIVE LIABILITIES	99	67
Derivatives designated as hedging instruments:
Derivative [Line Items]
DERIVATIVE ASSETS	225	155
DERIVATIVE LIABILITIES	96	65
Derivatives designated as hedging instruments: | Foreign currency derivatives | Other current assets
Derivative [Line Items]
DERIVATIVE ASSETS	8	7
Derivatives designated as hedging instruments: | Foreign currency derivatives | Other current liabilities
Derivative [Line Items]
DERIVATIVE LIABILITIES	46	6
Derivatives designated as hedging instruments: | Interest rate derivatives | Other assets
Derivative [Line Items]
DERIVATIVE ASSETS	217	148
Derivatives designated as hedging instruments: | Interest rate derivatives | Other long-term liabilities
Derivative [Line Items]
DERIVATIVE LIABILITIES	0	3
Derivatives designated as hedging instruments: | Equity derivatives | Other current assets
Derivative [Line Items]
DERIVATIVE ASSETS	0	0
Derivatives designated as hedging instruments: | Equity derivatives | Other current liabilities
Derivative [Line Items]
DERIVATIVE LIABILITIES	50	56
Derivatives not designated as hedging instruments:
Derivative [Line Items]
DERIVATIVE ASSETS	2	5
DERIVATIVE LIABILITIES	3	2
Derivatives not designated as hedging instruments: | Foreign currency derivatives | Other current assets
Derivative [Line Items]
DERIVATIVE ASSETS	2	3
Derivatives not designated as hedging instruments: | Foreign currency derivatives | Other current liabilities
Derivative [Line Items]
DERIVATIVE LIABILITIES	3	2
Derivatives not designated as hedging instruments: | Equity derivatives | Other assets
Derivative [Line Items]
DERIVATIVE ASSETS	0	2
Derivatives not designated as hedging instruments: | Equity derivatives | Other long-term liabilities
Derivative [Line Items]
DERIVATIVE LIABILITIES	$ 0	$ 0