Employees
| Concept | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2023-12-20 | As at 2022-12-20 | As at 2022-12-20 | As at 2021-12-20 | As at 2021-12-20 | As at 2020-12-20 | As at 2020-12-20 | As at 2019-12-20 | As at 2019-12-20 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Employees | |||||||||||||||||||||
| Information about reporting company | |||||||||||||||||||||
| Number of employees of reporting company | |||||||||||||||||||||
| Number of employees | 
                                                197
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                202
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                228
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                44
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                18
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                129
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                11
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                171
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                26
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                33
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                127
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                26
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                11
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                234
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                202
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                245
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                206
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                222
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                262
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                222
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                263
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |