Derivative Instruments (Derivatives Recorded At Fair Value) (Details) - USD ($) $ in Millions	Oct. 28, 2017	Jul. 29, 2017
Derivative [Line Items]
DERIVATIVE ASSETS	$ 99	$ 149
DERIVATIVE LIABILITIES	18	4
Derivatives designated as hedging instruments:
Derivative [Line Items]
DERIVATIVE ASSETS	98	148
DERIVATIVE LIABILITIES	16	1
Derivatives designated as hedging instruments: | Foreign currency derivatives | Other current assets
Derivative [Line Items]
DERIVATIVE ASSETS	40	46
Derivatives designated as hedging instruments: | Foreign currency derivatives | Other current liabilities
Derivative [Line Items]
DERIVATIVE LIABILITIES	0	1
Derivatives designated as hedging instruments: | Equity derivatives/warrants | Other current assets
Derivative [Line Items]
DERIVATIVE ASSETS	0	0
Derivatives designated as hedging instruments: | Equity derivatives/warrants | Other current liabilities
Derivative [Line Items]
DERIVATIVE LIABILITIES	14	0
Derivatives designated as hedging instruments: | Interest rate derivatives | Other assets
Derivative [Line Items]
DERIVATIVE ASSETS	58	102
Derivatives designated as hedging instruments: | Interest rate derivatives | Other long-term liabilities
Derivative [Line Items]
DERIVATIVE LIABILITIES	2	0
Derivatives not designated as hedging instruments:
Derivative [Line Items]
DERIVATIVE ASSETS	1	1
DERIVATIVE LIABILITIES	2	3
Derivatives not designated as hedging instruments: | Foreign currency derivatives | Other current assets
Derivative [Line Items]
DERIVATIVE ASSETS	1	1
Derivatives not designated as hedging instruments: | Foreign currency derivatives | Other current liabilities
Derivative [Line Items]
DERIVATIVE LIABILITIES	2	3
Derivatives not designated as hedging instruments: | Equity derivatives/warrants | Other assets
Derivative [Line Items]
DERIVATIVE ASSETS	0	0
Derivatives not designated as hedging instruments: | Equity derivatives/warrants | Other long-term liabilities
Derivative [Line Items]
DERIVATIVE LIABILITIES	$ 0	$ 0