Stock-based compensation - Classification of expense (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Share-Based Compensation | ||
| Stock-based compensation expense | $ 32,272 | $ 35,044 |
| Stock options | ||
| Share-Based Compensation | ||
| Stock-based compensation expense | 15,312 | 19,885 |
| Restricted and performance stock units | ||
| Share-Based Compensation | ||
| Stock-based compensation expense | 16,960 | 15,159 |
| Research and development | ||
| Share-Based Compensation | ||
| Stock-based compensation expense | 16,734 | 18,439 |
| Selling, general and administrative | ||
| Share-Based Compensation | ||
| Stock-based compensation expense | $ 15,538 | $ 16,605 |