Financing Receivables and Guarantees (Schedule Of Financing Receivables) (Detail) (USD $) In Millions, unless otherwise specified	Jul. 27, 2013	Jul. 28, 2012	Jul. 30, 2011	Jul. 31, 2010
Financing Receivables [Line Items]
Allowance for credit loss	$ (344)	$ (380)	$ (367)	$ (301)
Lease Receivables
Financing Receivables [Line Items]
Gross	3,780	3,429
Unearned income	(273)	(250)
Allowance for credit loss	(238)	(247)
Total, net	3,269	2,932
Current	1,418	1,200
Noncurrent	1,851	1,732
Loan Receivables
Financing Receivables [Line Items]
Gross	1,649	1,796
Allowance for credit loss	(86)	(122)
Total, net	1,563	1,674
Current	898	968
Noncurrent	665	706
Financed Service Contracts & Other
Financing Receivables [Line Items]
Gross	3,136	2,651
Allowance for credit loss	(20)	(11)
Total, net	3,116	2,640
Current	1,721	1,493
Noncurrent	1,395	1,147
Total Financing Receivables
Financing Receivables [Line Items]
Gross	8,565	7,876
Unearned income	(273)	(250)
Allowance for credit loss	(344)	(380)
Total, net	7,948	7,246
Current	4,037	3,661
Noncurrent	$ 3,911	$ 3,585