Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 26, 2014	Jul. 27, 2013	Jul. 28, 2012
Financing Receivables
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of fiscal year	$ 344	$ 380	$ 367
Provisions	14	11	31
Recoveries (write-offs), net	(9)	(46)	(3)
Foreign exchange and other		(1)	(15)
Balance at end of fiscal year	349	344	380
Accounts Receivable
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of fiscal year	228	207	204
Provisions	65	33	19
Recoveries (write-offs), net	(28)	(12)	(16)
Foreign exchange and other		0	0
Balance at end of fiscal year	$ 265	$ 228	$ 207