Financing Receivables And Guarantees (Allowance For Credit Loss And Related Financing Receivables) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Apr. 26, 2014	Apr. 27, 2013	Apr. 26, 2014	Apr. 27, 2013	Jul. 27, 2013
Financing Receivable, Allowance for Credit losses [Line Items]
Financing Receivable, Allowance for Credit Losses	$ 374	$ 361	$ 344	$ 380
Provisions	(18)	44	14	20
Recoveries (write-offs), net		(44)		(44)
Recoveries (write-offs), net	2		3
Foreign exchange and other	2	(4)	(1)	1
Financing Receivable, Allowance for Credit Losses	360	357	360	357
Gross Receivables, Net of Unearned Income	7,968	8,073	7,968	8,073	8,292
Lease Receivables
Financing Receivable, Allowance for Credit losses [Line Items]
Financing Receivable, Allowance for Credit Losses	254	247	238	247
Provisions	(6)	30	9	27
Recoveries (write-offs), net	(1)	(29)	0	(29)
Foreign exchange and other	2	(3)	2	0
Financing Receivable, Allowance for Credit Losses	249	245	249	245
Gross Receivables, Net of Unearned Income	3,537	3,478	3,537	3,478	3,507
Loan Receivables
Financing Receivable, Allowance for Credit losses [Line Items]
Financing Receivable, Allowance for Credit Losses	98	101	86	122
Provisions	(10)	8	5	(15)
Recoveries (write-offs), net		(15)		(15)
Recoveries (write-offs), net	4		4
Foreign exchange and other	0	(1)	(3)	1
Financing Receivable, Allowance for Credit Losses	92	93	92	93
Gross Receivables, Net of Unearned Income	1,621	1,671	1,621	1,671	1,649
Financed Service Contracts And Other
Financing Receivable, Allowance for Credit losses [Line Items]
Financing Receivable, Allowance for Credit Losses	22	13	20	11
Provisions	(2)	6	0	8
Recoveries (write-offs), net	(1)	0	(1)	0
Foreign exchange and other	0	0	0	0
Financing Receivable, Allowance for Credit Losses	19	19	19	19
Gross Receivables, Net of Unearned Income	$ 2,810	$ 2,924	$ 2,810	$ 2,924	$ 3,136