Financing Receivables And Guarantees (Additional Information) (Detail) (USD $)	3 Months Ended
	Oct. 26, 2013 D	Oct. 27, 2012	Jul. 27, 2013
Financing Receivables And Guarantees [Line Items]
Average term of lease arrangements, years	4 years
Term of Loan Receivable Arrangement	3 years
Financing receivable, allowance for credit loss and deferred revenue	$ 2,289,000,000		$ 2,453,000,000
Gross Financing Receivable, Net of Unearned	8,375,000,000	7,795,000,000	8,292,000,000
Threshold period for past due receivables, days	31 days
Unbilled Or Current In Greater Than Ninety Days Past Due	320,000,000		406,000,000
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	92,000,000		87,000,000
Risk rating for receivables deemed to be impaired, minimum	8
Channel partners revolving short-term financing payment term, minimum (days)	60
Channel partners revolving short-term financing payment term, maximum (days)	90
Volume of channel partner financing	6,300,000,000	5,600,000,000
Balance of the channel partner financing subject to guarantees	1,400,000,000		1,400,000,000
End User Lease And Loan Term Maximum	3 years
Financing provided by third parties for leases and loans on which the Company has provided guarantees	25,000,000	44,000,000
Minimum [Member]
Financing Receivables And Guarantees [Line Items]
Financing Receivable, Credit Quality, Additional Information	1
Maximum [Member]
Financing Receivables And Guarantees [Line Items]
Financing Receivable, Credit Quality, Additional Information	10
Financed Service Contracts And Other
Financing Receivables And Guarantees [Line Items]
Deferred Service Revenue related to financed service contracts and other	$ 1,881,000,000		$ 2,036,000,000
Financed Service Contracts And Other | Minimum [Member]
Financing Receivables And Guarantees [Line Items]
Services revenue recognized ratably, in years	1 year
Financed Service Contracts And Other | Maximum [Member]
Financing Receivables And Guarantees [Line Items]
Services revenue recognized ratably, in years	3 years
Pass [Member] | Minimum [Member]
Financing Receivables And Guarantees [Line Items]
Financing Receivable, Credit Quality, Additional Information	1
Pass [Member] | Maximum [Member]
Financing Receivables And Guarantees [Line Items]
Financing Receivable, Credit Quality, Additional Information	4
Special Mention [Member] | Minimum [Member]
Financing Receivables And Guarantees [Line Items]
Financing Receivable, Credit Quality, Additional Information	5
Special Mention [Member] | Maximum [Member]
Financing Receivables And Guarantees [Line Items]
Financing Receivable, Credit Quality, Additional Information	6
Substandard [Member] | Minimum [Member]
Financing Receivables And Guarantees [Line Items]
Financing Receivable, Credit Quality, Additional Information	7