Intangible assets and goodwill - Schedule of Impaired Intangible Assets (Details) - In Process Research and Development [Member] - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
|
| Intangible assets – in-process research and development | ||
| Balance | $ 41,128 | $ 41,128 |
| Impairment | 0 | 0 |
| Balance | 41,128 | 41,128 |
| GTX-104 [Member] | ||
| Intangible assets – in-process research and development | ||
| Balance | 27,595 | 27,595 |
| Impairment | 0 | 0 |
| Balance | 27,595 | 27,595 |
| GTX-102 [Member] | ||
| Intangible assets – in-process research and development | ||
| Balance | 9,196 | 9,196 |
| Impairment | 0 | 0 |
| Balance | 9,196 | 9,196 |
| GTX-101 [Member] | ||
| Intangible assets – in-process research and development | ||
| Balance | 4,337 | 4,337 |
| Impairment | 0 | 0 |
| Balance | $ 4,337 | $ 4,337 |