Financing Receivables - Schedule of Aging Analysis of Financing Receivables (Details) - USD ($) $ in Millions	Jan. 23, 2021	Jul. 25, 2020
Financing Receivable, Past Due [Line Items]
Total Past Due	$ 528	$ 677
Current	9,632	10,103
Gross	10,160	10,780
120+ Still Accruing	48	67
Nonaccrual Financing Receivables	87	112
Impaired Financing Receivables	87	112
Past due 31-60 days
Financing Receivable, Past Due [Line Items]
Total Past Due	217	227
Past due 61-90 days
Financing Receivable, Past Due [Line Items]
Total Past Due	54	200
Past due 91 or above days
Financing Receivable, Past Due [Line Items]
Total Past Due	257	250
Lease Receivables
Financing Receivable, Past Due [Line Items]
Total Past Due	164	124
Current	1,604	1,889
Gross	1,768	2,013
120+ Still Accruing	2
Nonaccrual Financing Receivables	33	43
Impaired Financing Receivables	33	43
Lease Receivables | Past due 31-60 days
Financing Receivable, Past Due [Line Items]
Total Past Due	68	29
Lease Receivables | Past due 61-90 days
Financing Receivable, Past Due [Line Items]
Total Past Due	13	47
Lease Receivables | Past due 91 or above days
Financing Receivable, Past Due [Line Items]
Total Past Due	83	48
Loan Receivables
Financing Receivable, Past Due [Line Items]
Total Past Due	212	285
Current	5,605	5,652
Gross	5,817	5,937
120+ Still Accruing	15
Nonaccrual Financing Receivables	50	65
Impaired Financing Receivables	50	65
Loan Receivables | Past due 31-60 days
Financing Receivable, Past Due [Line Items]
Total Past Due	109	129
Loan Receivables | Past due 61-90 days
Financing Receivable, Past Due [Line Items]
Total Past Due	30	78
Loan Receivables | Past due 91 or above days
Financing Receivable, Past Due [Line Items]
Total Past Due	73	78
Financed Service Contracts
Financing Receivable, Past Due [Line Items]
Total Past Due	152	268
Current	2,423	2,562
Gross	2,575	2,830
120+ Still Accruing	31
Nonaccrual Financing Receivables	4	4
Impaired Financing Receivables	4	4
Financed Service Contracts | Past due 31-60 days
Financing Receivable, Past Due [Line Items]
Total Past Due	40	69
Financed Service Contracts | Past due 61-90 days
Financing Receivable, Past Due [Line Items]
Total Past Due	11	75
Financed Service Contracts | Past due 91 or above days
Financing Receivable, Past Due [Line Items]
Total Past Due	$ 101	$ 124