Finance Receivables, Net - Aging of Amortized Cost Basis of Finance Receivables by Class (Details) - USD ($) $ in Millions	Dec. 31, 2022	Mar. 31, 2022
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	$ 90,778	$ 83,678
90 Days or greater past due and accruing	152	65
30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	1,439	932
60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	432	242
90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	217	117
Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	2,088	1,291
Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	88,690	82,387
Retail Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	78,977	73,380
90 Days or greater past due and accruing	152	65
Retail Loan [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	1,439	932
Retail Loan [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	432	242
Retail Loan [Member] | 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	217	117
Retail Loan [Member] | Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	2,088	1,291
Retail Loan [Member] | Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	76,889	72,089
Wholesale [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	3,890	2,943
90 Days or greater past due and accruing	0	0
Wholesale [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Wholesale [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Wholesale [Member] | 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Wholesale [Member] | Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Wholesale [Member] | Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	3,890	2,943
Real estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	4,897	5,019
90 Days or greater past due and accruing	0	0
Real estate [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Real estate [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Real estate [Member] | 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Real estate [Member] | Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Real estate [Member] | Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	4,897	5,019
Working capital [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	3,014	2,336
90 Days or greater past due and accruing	0	0
Working capital [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Working capital [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Working capital [Member] | 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Working capital [Member] | Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	0	0
Working capital [Member] | Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	$ 3,014	$ 2,336