Stock-based compensation - Classification of expense (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
|
| Share-Based Compensation | ||||
| Stock-based compensation expense | $ 10,545 | $ 8,338 | $ 18,219 | $ 17,100 |
| Stock options | ||||
| Share-Based Compensation | ||||
| Stock-based compensation expense | 3,363 | 4,161 | 6,823 | 8,298 |
| Restricted and performance stock units | ||||
| Share-Based Compensation | ||||
| Stock-based compensation expense | 7,182 | 4,177 | 11,396 | 8,802 |
| Income Statement Location [Axis]: us-gaap:ResearchAndDevelopmentExpense | ||||
| Share-Based Compensation | ||||
| Stock-based compensation expense | 4,854 | 4,379 | 8,461 | 9,068 |
| Income Statement Location [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense | ||||
| Share-Based Compensation | ||||
| Stock-based compensation expense | $ 5,691 | $ 3,959 | $ 9,758 | $ 8,032 |