Employees
| Concept | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2021-03-31 | As at 2021-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|
| Employees | |||||||||||
| Information about group | |||||||||||
| Number of employees of group | |||||||||||
| Number of employees | 
                                                288
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,207
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                522
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                47
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,078
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,098
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                35
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                37
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,108
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,125
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                30
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | — | 
                                                148
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                116
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                116
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                112
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                104
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — |