Investment in Operating Leases - Leased Vehicle Expense (Detail) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
Mar. 31, 2023 |
|
| Lessor, Lease, Description [Line Items] | |||
| End of term charges | $ 8 | $ 6 | $ 2 |
| Leased Vehicles | |||
| Lessor, Lease, Description [Line Items] | |||
| Depreciation expense | 4,348 | 4,343 | 4,872 |
| Initial direct costs and other lessor costs | 126 | 119 | 134 |
| Gain on disposition of leased vehicles | (84) | (122) | (115) |
| Total leased vehicle expenses, net | $ 4,390 | $ 4,340 | $ 4,891 |