Financing Receivables and Operating Leases (Additional Information) (Details) (USD $)	12 Months Ended
	Jul. 26, 2014		Jul. 27, 2013		Jul. 28, 2012
Financing Receivables And Guarantees [Line Items]
Average lease term (in years)	4 years
Loan receivables term (in years)	3 years
Deferred revenue:	$ 14,142,000,000		$ 13,423,000,000
Financing receivable, allowance for credit loss and deferred revenue	2,220,000,000		2,453,000,000
Total financing receivables before allowance for credit loss	8,420,000,000	[1]	8,292,000,000	[1]	7,626,000,000	[1]
Threshold for past due receivables (in days)	31 days
Unbilled or current financing receivables included in greater than 91 days plus past due	296,000,000		406,000,000
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	116,000,000		87,000,000
Minimum future rentals from operating leases (per year amount in Fiscal 2015)	200,000,000
Minimum future rental from operating leases (per year amount in Fiscal 2016)	100,000,000
Lease Receivables
Financing Receivables And Guarantees [Line Items]
Total financing receivables before allowance for credit loss	3,527,000,000	[1]	3,507,000,000	[1]	3,179,000,000	[1]
Loan Receivables
Financing Receivables And Guarantees [Line Items]
Total financing receivables before allowance for credit loss	1,683,000,000	[1]	1,649,000,000	[1]	1,796,000,000	[1]
Financed Service Contracts and Other
Financing Receivables And Guarantees [Line Items]
Deferred revenue:	1,843,000,000		2,036,000,000
Total financing receivables before allowance for credit loss	3,210,000,000	[1]	3,136,000,000	[1]	2,651,000,000	[1]
Minimum
Financing Receivables And Guarantees [Line Items]
Financed service contracts term (in years)	1 year
Minimum | Financed Service Contracts and Other
Financing Receivables And Guarantees [Line Items]
Financed service contracts term (in years)	1 year
Minimum | Pass
Financing Receivables And Guarantees [Line Items]
Financing credit risk rating-investment-lowest	1
Minimum | Special Mention
Financing Receivables And Guarantees [Line Items]
Financing credit risk rating-investment-lowest	5
Minimum | Substandard
Financing Receivables And Guarantees [Line Items]
Financing credit risk rating-investment-lowest	7
Maximum
Financing Receivables And Guarantees [Line Items]
Loan receivables term (in years)	3 years
Financed service contracts term (in years)	3 years
Minimum future rentals from operating leases (per year amount in Fiscal 2017)	100,000,000
Minimum future rentals from operating leases (per year amount in Fiscal 2018)	100,000,000
Minimum future rentals from operating leases (per year amount in Fiscal 2019)	$ 100,000,000
Maximum | Financed Service Contracts and Other
Financing Receivables And Guarantees [Line Items]
Financed service contracts term (in years)	3 years
Maximum | Pass
Financing Receivables And Guarantees [Line Items]
Financing credit risk rating-investment-lowest	4
Maximum | Special Mention
Financing Receivables And Guarantees [Line Items]
Financing credit risk rating-investment-lowest	6

[1] Total financing receivables before allowance for credit loss.