Financing Receivables and Operating Leases (Summary Of Allowances For Credit Loss And Related Financing Receivables) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 26, 2014		Jul. 27, 2013		Jul. 28, 2012
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit loss as of	$ 344		$ 380		$ 367
Provisions	(14)		11		31
Recoveries (write-offs), net	(9)		(46)		(3)
Foreign exchange and other	0		(1)		(15)
Allowance for credit loss as of	349		344		380
Total financing receivables before allowance for credit loss	8,420	[1]	8,292	[1]	7,626	[1]
Lease Receivables
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit loss as of	238		247		237
Provisions	(4)		21		22
Recoveries (write-offs), net	(11)		(30)		(2)
Foreign exchange and other	(2)		0		(10)
Allowance for credit loss as of	233		238		247
Total financing receivables before allowance for credit loss	3,527	[1]	3,507	[1]	3,179	[1]
Loan Receivables
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit loss as of	86		122		103
Provisions	(9)		(20)		22
Recoveries (write-offs), net			(15)		0
Financing Receivable, Allowance for Credit Losses, Recovery	5
Foreign exchange and other	2		(1)		(3)
Allowance for credit loss as of	98		86		122
Total financing receivables before allowance for credit loss	1,683	[1]	1,649	[1]	1,796	[1]
Financed Service Contracts and Other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit loss as of	20		11		27
Provisions	(1)		10		(13)
Recoveries (write-offs), net	(3)		(1)		(1)
Foreign exchange and other	0		0		(2)
Allowance for credit loss as of	18		20		11
Total financing receivables before allowance for credit loss	$ 3,210	[1]	$ 3,136	[1]	$ 2,651	[1]

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