Employees
| Concept | As at 2024-09-30 | As at 2024-09-30 | As at 2024-03-31 | As at 2024-03-31 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-03-31 | As at 2023-03-31 | 
|---|---|---|---|---|---|---|---|---|
| Employees | ||||||||
| Information about reporting company | ||||||||
| Number of employees of reporting company | ||||||||
| Number of employees | 
                                                1,105
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                925
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                877
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,056
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,071
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                901
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,001
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                827
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                201
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                180
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                176
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                192
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                183
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                168
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                172
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                161
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |