v3.26.1
Summary of significant accounting policies (Details)
$ in Thousands
12 Months Ended
Mar. 31, 2026
USD ($)
Segment
Jun. 30, 2026
USD ($)
Mar. 31, 2025
USD ($)
Mar. 31, 2024
USD ($)
Summary of significant accounting policies [Abstract]        
Number of operating segments (in Segment) | Segment 1      
In Process Research and Development [Member]        
Summary of significant accounting policies [Abstract]        
IPR&D asset $ 41,128   $ 41,128 $ 41,128
GTX 102 [Member] | In Process Research and Development [Member] | Forecast [Member]        
Summary of significant accounting policies [Abstract]        
IPR&D asset   $ 9,196    
GTX 101 [Member] | In Process Research and Development [Member] | Forecast [Member]        
Summary of significant accounting policies [Abstract]        
IPR&D asset   $ 4,337