Financing Receivables and Operating Leases (Schedule Of Financing Receivables Categorized By Internal Credit Risk Rating) (Details) - USD ($) $ in Millions	Jul. 30, 2016	Jul. 25, 2015
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	$ 8,603	$ 8,507
1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	4,766	4,609
5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	3,532	3,554
7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	305	344
Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	8,603	8,507
Leases Receivables | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	1,703	1,688
Leases Receivables | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	1,294	1,342
Leases Receivables | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	101	141
Leases Receivables | Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	3,098	3,171
Loan Receivables | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	986	788
Loan Receivables | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	967	823
Loan Receivables | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	182	152
Loan Receivables | Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	2,135	1,763
Financed Service Contracts and Other | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	2,077	2,133
Financed Service Contracts and Other | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	1,271	1,389
Financed Service Contracts and Other | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	22	51
Financed Service Contracts and Other | Total
Financing Receivable, Recorded Investment [Line Items]
FInancing receivables net of unearned income	$ 3,370	$ 3,573