Financing Receivables and Operating Leases - Schedule of Aging Analysis of Financing Receivables (Details) - USD ($) $ in Millions	Jul. 27, 2019	Jul. 28, 2018
Financing Receivable, Past Due [Line Items]
Total Past Due	$ 1,643	$ 1,185
Current	8,394	8,687
Total	10,037	9,872
Nonaccrual Financing Receivables	47	42
Impaired Financing Receivables	47	42
Past due 31 - 60 days
Financing Receivable, Past Due [Line Items]
Total Past Due	503	314
Past due 61 -90 days
Financing Receivable, Past Due [Line Items]
Total Past Due	240	160
Past due 91 or above days
Financing Receivable, Past Due [Line Items]
Total Past Due	900	711
Lease receivables
Financing Receivable, Past Due [Line Items]
Total Past Due	434	254
Current	1,796	2,293
Total	2,230	2,547
Nonaccrual Financing Receivables	13	9
Impaired Financing Receivables	13	9
Lease receivables | Past due 31 - 60 days
Financing Receivable, Past Due [Line Items]
Total Past Due	101	72
Lease receivables | Past due 61 -90 days
Financing Receivable, Past Due [Line Items]
Total Past Due	42	27
Lease receivables | Past due 91 or above days
Financing Receivable, Past Due [Line Items]
Total Past Due	291	155
Loan receivables
Financing Receivable, Past Due [Line Items]
Total Past Due	662	411
Current	4,776	4,588
Total	5,438	4,999
Nonaccrual Financing Receivables	31	30
Impaired Financing Receivables	31	30
Loan receivables | Past due 31 - 60 days
Financing Receivable, Past Due [Line Items]
Total Past Due	257	104
Loan receivables | Past due 61 -90 days
Financing Receivable, Past Due [Line Items]
Total Past Due	67	55
Loan receivables | Past due 91 or above days
Financing Receivable, Past Due [Line Items]
Total Past Due	338	252
Financed service contracts
Financing Receivable, Past Due [Line Items]
Total Past Due	547	520
Current	1,822	1,806
Total	2,369	2,326
Nonaccrual Financing Receivables	3	3
Impaired Financing Receivables	3	3
Financed service contracts | Past due 31 - 60 days
Financing Receivable, Past Due [Line Items]
Total Past Due	145	138
Financed service contracts | Past due 61 -90 days
Financing Receivable, Past Due [Line Items]
Total Past Due	131	78
Financed service contracts | Past due 91 or above days
Financing Receivable, Past Due [Line Items]
Total Past Due	$ 271	$ 304