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 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 | As at 2020-03-31 | As at 2020-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Employees | |||||||||||||
| Information about group | |||||||||||||
| Number of employees of group | |||||||||||||
| Number of employees | 
                                                844
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                244
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                244
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                955
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                111
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                947
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                240
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                255
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                924
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                825
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                270
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                272
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                809
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                106
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                65
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                65
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                109
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                153
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                91
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                79
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                120
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                124
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                89
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                123
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                160
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |