Financing Receivables - Schedule of Financing Receivables Categorized by Internal Credit Risk Rating (Details) - USD ($) $ in Millions	Apr. 30, 2022	Jul. 31, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	$ 18	$ 8
Origination year - Fiscal Year 2018/2017	160	190
Origination year - Fiscal Year 2019/2018	573	437
Origination year - Fiscal Year 2020/2019	1,466	1,413
Origination year - Fiscal Year 2021/2020	2,898	2,689
Origination year - Fiscal Year 2022/2021	2,690	4,551
Gross	7,805	9,288
Lease Receivables
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	7	3
Origination year - Fiscal Year 2018/2017	57	39
Origination year - Fiscal Year 2019/2018	178	171
Origination year - Fiscal Year 2020/2019	333	367
Origination year - Fiscal Year 2021/2020	378	590
Origination year - Fiscal Year 2022/2021	292	462
Gross	1,245	1,632
Loan Receivables
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	9	5
Origination year - Fiscal Year 2018/2017	86	107
Origination year - Fiscal Year 2019/2018	293	213
Origination year - Fiscal Year 2020/2019	894	829
Origination year - Fiscal Year 2021/2020	1,601	1,538
Origination year - Fiscal Year 2022/2021	1,626	2,511
Gross	4,509	5,203
Financed Service Contracts
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	2	0
Origination year - Fiscal Year 2018/2017	17	44
Origination year - Fiscal Year 2019/2018	102	53
Origination year - Fiscal Year 2020/2019	239	217
Origination year - Fiscal Year 2021/2020	919	561
Origination year - Fiscal Year 2022/2021	772	1,578
Gross	2,051	2,453
1 to 4 | Lease Receivables
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	3	2
Origination year - Fiscal Year 2018/2017	38	20
Origination year - Fiscal Year 2019/2018	90	100
Origination year - Fiscal Year 2020/2019	144	168
Origination year - Fiscal Year 2021/2020	192	282
Origination year - Fiscal Year 2022/2021	152	227
Gross	619	799
1 to 4 | Loan Receivables
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	6	4
Origination year - Fiscal Year 2018/2017	63	86
Origination year - Fiscal Year 2019/2018	173	134
Origination year - Fiscal Year 2020/2019	565	577
Origination year - Fiscal Year 2021/2020	1,018	990
Origination year - Fiscal Year 2022/2021	979	1,552
Gross	2,804	3,343
1 to 4 | Financed Service Contracts
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	1	0
Origination year - Fiscal Year 2018/2017	5	38
Origination year - Fiscal Year 2019/2018	52	26
Origination year - Fiscal Year 2020/2019	99	106
Origination year - Fiscal Year 2021/2020	624	252
Origination year - Fiscal Year 2022/2021	567	1,053
Gross	1,348	1,475
5 to 6 | Lease Receivables
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	3	1
Origination year - Fiscal Year 2018/2017	18	17
Origination year - Fiscal Year 2019/2018	83	65
Origination year - Fiscal Year 2020/2019	176	187
Origination year - Fiscal Year 2021/2020	183	285
Origination year - Fiscal Year 2022/2021	129	231
Gross	592	786
5 to 6 | Loan Receivables
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	2	0
Origination year - Fiscal Year 2018/2017	22	19
Origination year - Fiscal Year 2019/2018	94	75
Origination year - Fiscal Year 2020/2019	289	202
Origination year - Fiscal Year 2021/2020	547	505
Origination year - Fiscal Year 2022/2021	637	925
Gross	1,591	1,726
5 to 6 | Financed Service Contracts
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	1	0
Origination year - Fiscal Year 2018/2017	12	6
Origination year - Fiscal Year 2019/2018	47	26
Origination year - Fiscal Year 2020/2019	135	105
Origination year - Fiscal Year 2021/2020	292	302
Origination year - Fiscal Year 2022/2021	202	520
Gross	689	959
7 and Higher | Lease Receivables
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	1	0
Origination year - Fiscal Year 2018/2017	1	2
Origination year - Fiscal Year 2019/2018	5	6
Origination year - Fiscal Year 2020/2019	13	12
Origination year - Fiscal Year 2021/2020	3	23
Origination year - Fiscal Year 2022/2021	11	4
Gross	34	47
7 and Higher | Loan Receivables
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	1	1
Origination year - Fiscal Year 2018/2017	1	2
Origination year - Fiscal Year 2019/2018	26	4
Origination year - Fiscal Year 2020/2019	40	50
Origination year - Fiscal Year 2021/2020	36	43
Origination year - Fiscal Year 2022/2021	10	34
Gross	114	134
7 and Higher | Financed Service Contracts
Financing Receivable, Credit Quality Indicator [Line Items]
Origination year - Prior	0	0
Origination year - Fiscal Year 2018/2017	0	0
Origination year - Fiscal Year 2019/2018	3	1
Origination year - Fiscal Year 2020/2019	5	6
Origination year - Fiscal Year 2021/2020	3	7
Origination year - Fiscal Year 2022/2021	3	5
Gross	$ 14	$ 19