Employees
| Concept | 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 | 
                                                3,430
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,430
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2,254
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2,135
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,317
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,380
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,848
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,450
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2,928
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2,853
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,407
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                455
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                455
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                134
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                492
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                492
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                356
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                353
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                177
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
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