Employee Termination Benefits - Additional Information (Detail) - USD ($) $ in Millions |
12 Months Ended | 14 Months Ended | |
|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Sep. 30, 2025 |
|
| Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | |||
| Restructuring cost and reserve | $ 5.9 | ||
| Location, Statement of Income, Balance [Axis]: us-gaap:GeneralAndAdministrativeExpense | |||
| Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | |||
| Restructuring cost and reserve | $ 0.1 | $ 3.9 | |
| Location, Statement of Income, Balance [Axis]: us-gaap:ResearchAndDevelopmentExpense | |||
| Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | |||
| Restructuring cost and reserve | $ 0.0 | $ 1.8 | |