Financing Receivables - Schedule of Financing Receivables Categorized by Internal Credit Risk Rating (Details) - USD ($) $ in Millions	Jul. 31, 2021	Jul. 25, 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	$ 8
Origination year - Fiscal Year 2017	190
Origination year - Fiscal Year 2018	437
Origination year - Fiscal Year 2019	1,413
Origination year - Fiscal Year 2020	2,689
Origination year - Fiscal Year 2021	4,551
Total	9,288	$ 10,780
1 to 4
Financing Receivable, Credit Quality Indicator [Line Items]
Total		6,445
5 to 6
Financing Receivable, Credit Quality Indicator [Line Items]
Total		4,066
7 and Higher
Financing Receivable, Credit Quality Indicator [Line Items]
Total		269
Lease receivables
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	3
Origination year - Fiscal Year 2017	39
Origination year - Fiscal Year 2018	171
Origination year - Fiscal Year 2019	367
Origination year - Fiscal Year 2020	590
Origination year - Fiscal Year 2021	462
Total	1,632	2,013
Lease receivables \| 1 to 4
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	2
Origination year - Fiscal Year 2017	20
Origination year - Fiscal Year 2018	100
Origination year - Fiscal Year 2019	168
Origination year - Fiscal Year 2020	282
Origination year - Fiscal Year 2021	227
Total	799	992
Lease receivables \| 5 to 6
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	1
Origination year - Fiscal Year 2017	17
Origination year - Fiscal Year 2018	65
Origination year - Fiscal Year 2019	187
Origination year - Fiscal Year 2020	285
Origination year - Fiscal Year 2021	231
Total	786	952
Lease receivables \| 7 and Higher
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	0
Origination year - Fiscal Year 2017	2
Origination year - Fiscal Year 2018	6
Origination year - Fiscal Year 2019	12
Origination year - Fiscal Year 2020	23
Origination year - Fiscal Year 2021	4
Total	47	69
Loan receivables
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	5
Origination year - Fiscal Year 2017	107
Origination year - Fiscal Year 2018	213
Origination year - Fiscal Year 2019	829
Origination year - Fiscal Year 2020	1,538
Origination year - Fiscal Year 2021	2,511
Total	5,203	5,937
Loan receivables \| 1 to 4
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	4
Origination year - Fiscal Year 2017	86
Origination year - Fiscal Year 2018	134
Origination year - Fiscal Year 2019	577
Origination year - Fiscal Year 2020	990
Origination year - Fiscal Year 2021	1,552
Total	3,343	3,808
Loan receivables \| 5 to 6
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	0
Origination year - Fiscal Year 2017	19
Origination year - Fiscal Year 2018	75
Origination year - Fiscal Year 2019	202
Origination year - Fiscal Year 2020	505
Origination year - Fiscal Year 2021	925
Total	1,726	1,961
Loan receivables \| 7 and Higher
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	1
Origination year - Fiscal Year 2017	2
Origination year - Fiscal Year 2018	4
Origination year - Fiscal Year 2019	50
Origination year - Fiscal Year 2020	43
Origination year - Fiscal Year 2021	34
Total	134	168
Financed service contracts
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	0
Origination year - Fiscal Year 2017	44
Origination year - Fiscal Year 2018	53
Origination year - Fiscal Year 2019	217
Origination year - Fiscal Year 2020	561
Origination year - Fiscal Year 2021	1,578
Total	2,453	2,830
Financed service contracts \| 1 to 4
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	0
Origination year - Fiscal Year 2017	38
Origination year - Fiscal Year 2018	26
Origination year - Fiscal Year 2019	106
Origination year - Fiscal Year 2020	252
Origination year - Fiscal Year 2021	1,053
Total	1,475	1,645
Financed service contracts \| 5 to 6
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	0
Origination year - Fiscal Year 2017	6
Origination year - Fiscal Year 2018	26
Origination year - Fiscal Year 2019	105
Origination year - Fiscal Year 2020	302
Origination year - Fiscal Year 2021	520
Total	959	1,153
Financed service contracts \| 7 and Higher
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	0
Origination year - Fiscal Year 2017	0
Origination year - Fiscal Year 2018	1
Origination year - Fiscal Year 2019	6
Origination year - Fiscal Year 2020	7
Origination year - Fiscal Year 2021	5
Total	$ 19	$ 32

Amount of financing receivable originated more than five years prior to current fiscal year.

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Amount of financing receivable originated three years prior to current fiscal year.

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Amount of financing receivable originated two years prior to current fiscal year.

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Amount, before allowance for credit loss, of financing receivable.

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