Finance Receivables, Net - Schedule of Amortized Cost Basis of Retail Loan Portfolio and Dealer Products Portfolio by Credit Quality Indicator (Details) - USD ($) $ in Millions	Mar. 31, 2023	Mar. 31, 2022
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	$ 2,180	$ 2,279
Year two, originated, fiscal year before current fiscal year	1,349	1,567
Year three, originated, two years before current fiscal year	1,241	473
Year four, originated, three years before current fiscal year	264	542
Year five, originated, four years before current fiscal year	424	297
Originated, more than five years before current fiscal year	940	1,423
Revolving loans	5,725	3,717
Total	12,123	10,298
Retail Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	32,820	32,758
Year two, originated, fiscal year before current fiscal year	23,222	9,834
Year three, originated, two years before current fiscal year	14,678	4,913
Year four, originated, three years before current fiscal year	5,731	22,342
Year five, originated, four years before current fiscal year	2,279	2,761
Originated, more than five years before current fiscal year	916	772
Total	79,646	73,380
Current [Member] | Retail Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	32,377	32,382
Year two, originated, fiscal year before current fiscal year	22,585	9,624
Year three, originated, two years before current fiscal year	14,278	4,774
Year four, originated, three years before current fiscal year	5,555	21,917
Year five, originated, four years before current fiscal year	2,178	2,674
Originated, more than five years before current fiscal year	846	718
Total	77,819	72,089
30-59 Days Past Due [Member] | Retail Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	306	275
Year two, originated, fiscal year before current fiscal year	439	153
Year three, originated, two years before current fiscal year	285	101
Year four, originated, three years before current fiscal year	125	304
Year five, originated, four years before current fiscal year	71	63
Originated, more than five years before current fiscal year	44	36
Total	1,270	932
60-89 Days Past Due [Member] | Retail Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	90	68
Year two, originated, fiscal year before current fiscal year	135	40
Year three, originated, two years before current fiscal year	82	25
Year four, originated, three years before current fiscal year	35	82
Year five, originated, four years before current fiscal year	21	16
Originated, more than five years before current fiscal year	15	11
Total	378	242
90 Days or Greater Past Due [Member] | Retail Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	47	33
Year two, originated, fiscal year before current fiscal year	63	17
Year three, originated, two years before current fiscal year	33	13
Year four, originated, three years before current fiscal year	16	39
Year five, originated, four years before current fiscal year	9	8
Originated, more than five years before current fiscal year	11	7
Total	179	117
Wholesale [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year		0
Year two, originated, fiscal year before current fiscal year	0	0
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	0
Revolving loans	3,964	2,943
Total	3,964	2,943
Wholesale [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	0	0
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	0
Revolving loans	3,859	2,927
Total	3,859	2,927
Wholesale [Member] | Credit Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	0	0
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	0
Revolving loans	0	16
Total	0	16
Wholesale [Member] | At Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	0	0
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	0
Revolving loans	0	0
Total	1	0
Wholesale [Member] | Default [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	0	0
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	0
Revolving loans	0	0
Total	0	0
Real estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	1,391	1,616
Year two, originated, fiscal year before current fiscal year	1,031	1,245
Year three, originated, two years before current fiscal year	1,059	264
Year four, originated, three years before current fiscal year	133	384
Year five, originated, four years before current fiscal year	300	260
Originated, more than five years before current fiscal year	852	1,250
Revolving loans	209	0
Total	4,975	5,019
Real estate [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	1,378	1,614
Year two, originated, fiscal year before current fiscal year	1,024	1,245
Year three, originated, two years before current fiscal year	182	264
Year four, originated, three years before current fiscal year	131	384
Year five, originated, four years before current fiscal year	124	260
Originated, more than five years before current fiscal year	88	1,245
Revolving loans	1,552	0
Total	3,183	5,012
Real estate [Member] | Credit Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	5	2
Year two, originated, fiscal year before current fiscal year	0	0
Year three, originated, two years before current fiscal year	2	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	5
Revolving loans	0	0
Total	7	7
Real estate [Member] | At Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	8	0
Year two, originated, fiscal year before current fiscal year	7	0
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	0
Revolving loans	51	0
Total	51	0
Real estate [Member] | Default [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	0	0
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	0
Revolving loans	0	0
Total	0	0
Working capital [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	789	663
Year two, originated, fiscal year before current fiscal year	318	322
Year three, originated, two years before current fiscal year	182	209
Year four, originated, three years before current fiscal year	131	158
Year five, originated, four years before current fiscal year	124	37
Originated, more than five years before current fiscal year	88	173
Revolving loans	1,552	774
Total	3,184	2,336
Working capital [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	789	662
Year two, originated, fiscal year before current fiscal year	317	321
Year three, originated, two years before current fiscal year	1,057	209
Year four, originated, three years before current fiscal year	133	158
Year five, originated, four years before current fiscal year	300	37
Originated, more than five years before current fiscal year	850	173
Revolving loans	209	774
Total	4,951	2,334
Working capital [Member] | Credit Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	0	1
Year two, originated, fiscal year before current fiscal year	0	1
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	0
Revolving loans	54	0
Total	54	2
Working capital [Member] | At Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	1	0
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	2	0
Revolving loans	0	0
Total	17	0
Working capital [Member] | Default [Member]
Financing Receivable, Recorded Investment [Line Items]
Year one, originated, current fiscal year	0	0
Year two, originated, fiscal year before current fiscal year	0	0
Year three, originated, two years before current fiscal year	0	0
Year four, originated, three years before current fiscal year	0	0
Year five, originated, four years before current fiscal year	0	0
Originated, more than five years before current fiscal year	0	0
Revolving loans	0	0
Total	$ 0	$ 0