Financing Receivables and Operating Leases (Schedule Of Aging Analysis Of Financing Receivables) (Details) - USD ($) $ in Millions	Jul. 30, 2016	Jul. 25, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 1,393	$ 1,313
Current	7,210	7,194
FInancing receivables net of unearned income	8,603	8,507
Nonaccrual Financing Receivables	132	134
Impaired Financing Receivables	112	114
Past due 31 - 60 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	354	507
Past due 61 -90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	186	182
Past due 91 or above days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	853	624
Leases Receivables
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	387	302
Current	2,711	2,869
FInancing receivables net of unearned income	3,098	3,171
Nonaccrual Financing Receivables	60	73
Impaired Financing Receivables	60	73
Leases Receivables | Past due 31 - 60 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	111	90
Leases Receivables | Past due 61 -90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	25	27
Leases Receivables | Past due 91 or above days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	251	185
Loan Receivables
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	76	49
Current	2,059	1,714
FInancing receivables net of unearned income	2,135	1,763
Nonaccrual Financing Receivables	42	32
Impaired Financing Receivables	42	32
Loan Receivables | Past due 31 - 60 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	30	21
Loan Receivables | Past due 61 -90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	9	3
Loan Receivables | Past due 91 or above days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	37	25
Financed Service Contracts and Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	930	962
Current	2,440	2,611
FInancing receivables net of unearned income	3,370	3,573
Nonaccrual Financing Receivables	30	29
Impaired Financing Receivables	10	9
Financed Service Contracts and Other | Past due 31 - 60 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	213	396
Financed Service Contracts and Other | Past due 61 -90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	152	152
Financed Service Contracts and Other | Past due 91 or above days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 565	$ 414