Statement Of Changes In Net Assets Available For Benefits [Abstract]
| Concept | 
                                    
                                        2023-01-01 to 2023-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                        
|---|---|---|
| Statement of changes in net assets available for benefits [abstract] | ||
| Reconciliation of changes in net assets available for benefits [abstract] | ||
| Changes in net assets available for benefits [abstract] | ||
| Other income | 
                                        
                                             
                                                76,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                132,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Tax expense (income) | 
                                        
                                             
                                                2,515,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                2,689,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     |