Tax - Schedule of Gross Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2024 |
|
| Income Tax Uncertainties [Abstract] | |||
| Beginning unrecognized tax benefits/(expenses) | $ 1.1 | $ 1.1 | $ 1.0 |
| Increases related to prior year tax positions | 0.0 | 0.0 | 0.1 |
| Decreases related to prior year tax positions | (0.6) | 0.0 | 0.0 |
| Ending unrecognized tax benefits/(expenses) | $ 0.5 | $ 1.1 | $ 1.1 |