Employees
| Concept | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | 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 | 
                                                327
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                281
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                251
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                251
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                281
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                411
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,270
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                804
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                272
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                820
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,365
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,387
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                825
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                817
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,478
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,486
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                842
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                17
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                73
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                12
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                12
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                73
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                386
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                488
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                98
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                13
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                83
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                460
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                517
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                98
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                111
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                598
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                598
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                121
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |