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 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 | 
                                                301
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                84
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                160
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                269
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                65
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                545
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                382
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                48
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                370
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                522
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                518
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                370
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                366
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                504
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                503
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                368
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                11
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                24
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                613
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                10
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                21
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                648
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                351
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                320
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                357
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                668
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                693
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                392
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                403
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                708
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                685
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                399
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |