Financing Receivables and Operating Leases (Schedule Of Financing Receivables Categorized By Internal Credit Risk Rating) (Details) - USD ($) $ in Millions	Jan. 23, 2016	Jul. 25, 2015
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	$ 8,581	$ 8,507
1 to 4
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	5,020	4,609
5 to 6
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	3,260	3,554
7 and Higher
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	301	344
Total
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	8,581	8,507
Lease Receivables | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	1,640	1,688
Lease Receivables | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	1,245	1,342
Lease Receivables | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	114	141
Lease Receivables | Total
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	2,999	3,171
Loan Receivables | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	1,224	788
Loan Receivables | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	811	823
Loan Receivables | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	142	152
Loan Receivables | Total
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	2,177	1,763
Financed Service Contracts and Other | 1 to 4
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	2,156	2,133
Financed Service Contracts and Other | 5 to 6
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	1,204	1,389
Financed Service Contracts and Other | 7 and Higher
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	45	51
Financed Service Contracts and Other | Total
Financing Receivable, Recorded Investment [Line Items]
Gross receivables less unearned income	$ 3,405	$ 3,573