Financing Receivables and Operating Leases (Schedule Of Financing Receivables Categorized By Internal Credit Risk Rating) (Details) (USD $) In Millions, unless otherwise specified	Oct. 25, 2014		Jul. 26, 2014	Oct. 26, 2013
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	$ 8,090		$ 8,187
Total financing receivables before allowance for credit loss	8,324	[1]	8,420	8,375	[1]
1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	4,295		4,312
5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	3,415		3,498
7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	380		377
Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	8,090		8,187
Lease Receivables
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	3,275		3,294
Total financing receivables before allowance for credit loss	3,509	[1]		3,549	[1]
Lease Receivables | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	1,665		1,615
Lease Receivables | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	1,482		1,538
Lease Receivables | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	128		141
Lease Receivables | Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	3,275		3,294
Loan Receivables
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	1,744		1,683
Total financing receivables before allowance for credit loss	1,744	[1]		1,808	[1]
Loan Receivables | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	953		953
Loan Receivables | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	637		593
Loan Receivables | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	154		137
Loan Receivables | Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	1,744		1,683
Financed Service Contracts and Other
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	3,071		3,210
Total financing receivables before allowance for credit loss	3,071	[1]		3,018	[1]
Financed Service Contracts and Other | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	1,677		1,744
Financed Service Contracts and Other | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	1,296		1,367
Financed Service Contracts and Other | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	98		99
Financed Service Contracts and Other | Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables (including residual value, if any) net of deferred income	$ 3,071		$ 3,210

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