Employees
| Concept | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2023-03-31 | As at 2022-03-31 | As at 2021-03-31 | As at 2020-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Employees | ||||||||||||||||
| Information about group | ||||||||||||||||
| Number of employees of group | ||||||||||||||||
| Number of employees | 
                                                1,081
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                248
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,633
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                7,953
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                451
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                4,149
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                550
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                414
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                384
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                52
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2,257
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,594
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,538
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,612
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,624
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                81
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                15
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                207
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                840
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                35
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                583
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                149
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                166
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                264
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                275
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                226
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                201
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |