Financing Receivables And Guarantees (Schedule Of Financing Receivables By Portfolio Segment Aging Analysis) (Detail) (USD $) In Millions, unless otherwise specified	Oct. 26, 2013	Jul. 27, 2013	Oct. 27, 2012
Financing Receivable, Recorded Investment, Past Due [Line Items]
31 to 60 Days Past Due	$ 248	$ 166
61 to 90 Days Past Due	103	99
Greater Than 90 Days Past Due	441	527
Total Past Due	792	792
Class Of Financing Receivable Current	7,583	7,500
Gross Financing Receivable, Net of Unearned	8,375	8,292	7,795
Non-accrual financing receivables	47	56
Impaired Financing Receivables	52	42
Lease Receivables
Financing Receivable, Recorded Investment, Past Due [Line Items]
31 to 60 Days Past Due	135	85
61 to 90 Days Past Due	60	48
Greater Than 90 Days Past Due	148	124
Total Past Due	343	257
Class Of Financing Receivable Current	3,206	3,250
Gross Financing Receivable, Net of Unearned	3,549	3,507	3,340
Non-accrual financing receivables	28	27
Impaired Financing Receivables	24	22
Loan Receivables
Financing Receivable, Recorded Investment, Past Due [Line Items]
31 to 60 Days Past Due	28	6
61 to 90 Days Past Due	2	3
Greater Than 90 Days Past Due	16	11
Total Past Due	46	20
Class Of Financing Receivable Current	1,762	1,629
Gross Financing Receivable, Net of Unearned	1,808	1,649	1,816
Non-accrual financing receivables	7	11
Impaired Financing Receivables	17	9
Financed Service Contracts And Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
31 to 60 Days Past Due	85	75
61 to 90 Days Past Due	41	48
Greater Than 90 Days Past Due	277	392
Total Past Due	403	515
Class Of Financing Receivable Current	2,615	2,621
Gross Financing Receivable, Net of Unearned	3,018	3,136	2,639
Non-accrual financing receivables	12	18
Impaired Financing Receivables	$ 11	$ 11