Financing Receivables and Operating Leases (Schedule Of Financing Receivables Categorized By Internal Credit Risk Rating) (Details) - USD ($) $ in Millions	Jul. 25, 2015	Jul. 26, 2014
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	$ 8,507	$ 8,187
1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	4,609	4,312
5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	3,554	3,498
7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	344	377
Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	8,507	8,187
Leases Receivables | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	1,688	1,615
Leases Receivables | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	1,342	1,538
Leases Receivables | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	141	141
Leases Receivables | Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	3,171	3,294
Loan Receivables | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	788	953
Loan Receivables | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	823	593
Loan Receivables | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	152	137
Loan Receivables | Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	1,763	1,683
Financed Service Contracts and Other | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	2,133	1,744
Financed Service Contracts and Other | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	1,389	1,367
Financed Service Contracts and Other | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	51	99
Financed Service Contracts and Other | Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	$ 3,573	$ 3,210