Financing Receivables and Operating Leases (Summary Of Allowances For Credit Loss And Related Financing Receivables) (Details) - USD ($) $ in Millions	12 Months Ended
	Jul. 30, 2016	Jul. 25, 2015	Jul. 26, 2014
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit loss as of	$ 382	$ 349	$ 344
Provisions	17	57	14
write-offs, net	(15)	(7)	(9)
Foreign exchange and other	(9)	(17)	0
Allowance for credit loss as of	375	382	349
Lease Receivables
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit loss as of	259	233	238
Provisions	(13)	45	4
write-offs, net	(10)	(7)	(11)
Foreign exchange and other	(6)	(12)	2
Allowance for credit loss as of	230	259	233
Loan Receivables
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit loss as of	87	98	86
Provisions	13	(8)	9
Recoveries, net	0	1	5
Foreign exchange and other	(3)	(4)	(2)
Allowance for credit loss as of	97	87	98
Financed Service Contracts and Other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit loss as of	36	18	20
Provisions	17	20	1
write-offs, net	(5)	(1)	(3)
Foreign exchange and other	0	(1)	0
Allowance for credit loss as of	$ 48	$ 36	$ 18