Finance Receivables, Net - Aging of Amortized Cost Basis of Finance Receivables by Class (Details) - USD ($) $ in Millions	Mar. 31, 2023	Mar. 31, 2022
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	$ 91,769	$ 83,678
90 Days or greater past due and accruing	111	65
30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	1,270	932
60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	378	242
90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	179	117
Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	1,827	1,291
Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	89,942	82,387
Retail Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	79,646	73,380
90 Days or greater past due and accruing	111	65
Retail Loan [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	1,270	932
Retail Loan [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	378	242
Retail Loan [Member] | 90 Days or Greater Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	179	117
Retail Loan [Member] | Total Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	1,827	1,291
Retail Loan [Member] | Current [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	77,819	72,089
Wholesale [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	3,964	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	3,964	2,943
Real estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	4,975	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	4,975	5,019
Working capital [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Finance receivables	3,184	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	$ 3,184	$ 2,336