Valuation And Qualifying Accounts (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 27, 2013	Jul. 28, 2012	Jul. 30, 2011
Financing Receivable [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of fiscal year	$ 380	$ 367	$ 301
Provisions	11	31	82
Write-offs net of recoveries	(46)	(3)	(33)
Foreign exchange and other	(1)	(15)	17
Balance at end of fiscal year	344	380	367
Accounts Receivable
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of fiscal year	207	204	235
Provisions	33	19	7
Write-offs net of recoveries	(12)	(16)	(38)
Foreign exchange and other	0	0	0
Balance at end of fiscal year	$ 228	$ 207	$ 204