Finance Receivables, Net - Net Financing Receivables (Parenthetical) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Mar. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross finance receivables	$ 102,668	$ 103,393
Finance Receivables, Net [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross finance receivables	103,401	103,939
Finance Receivables, Net [Member] \| Securitized retail receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross finance receivables	$ 33,900	$ 34,400

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