Finance Receivables - Narrative (Detail) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
Mar. 31, 2023 |
|
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||
| Financing receivables | $ 52,516 | $ 47,248 | $ 37,585 |
| Retail loans and leases threshold delinquent (percent) (more than) | 10.00% | ||
| Retail | |||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||
| Financing receivables | $ 48,181 | 43,196 | |
| Collateral Pledged | Retail | |||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||
| Financing receivables | $ 13,000 | $ 9,800 |