Finance Receivables, Net - Net Financing Receivables (Parenthetical) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Mar. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross finance receivables	$ 105,417	$ 103,306
Finance Receivables, Net [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross finance receivables	105,892	103,331
Finance Receivables, Net [Member] \| Securitized retail receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross finance receivables	$ 33,400	$ 31,500

Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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+ Details