Stockholders' equity - Summary of share-based compensation expense (Detail) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2025 |
Dec. 31, 2024 |
|
| Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items] | ||||
| Share-based compensation expense | $ 7,379 | $ 3,138 | $ 12,559 | $ 3,573 |
| Research and development [Member] | ||||
| Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items] | ||||
| Share-based compensation expense | 2,667 | 436 | 3,535 | 549 |
| General and administrative [Member] | ||||
| Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items] | ||||
| Share-based compensation expense | $ 4,712 | $ 2,702 | $ 9,024 | $ 3,024 |