Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept | As at 2024-12-31 | As at 2023-12-31 | As at 2022-12-31 | 
|---|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | |||
| Property, plant and equipment [abstract] | |||
| Property, plant and equipment | 
                                                84,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                89,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Intangible assets and goodwill [abstract] | |||
| Goodwill | 
                                                2  607
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                2  607
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Investment property [abstract] | |||
| Investment property | 
                                                20  104
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                19  698
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Trade and other receivables [abstract] | |||
| Other receivables | 
                                                87,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                5,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Categories of non-current financial assets [abstract] | |||
| Non-current financial assets at fair value through other comprehensive income [abstract] | |||
| Non-current financial assets measured at fair value through other comprehensive income | 
                                                3  855
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                3  694
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Categories of current financial assets [abstract] | |||
| Current financial assets at fair value through profit or loss [abstract] | |||
| Current financial assets at fair value through profit or loss, designated upon initial recognition or subsequently | 
                                                17  367
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                13  489
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Categories of financial assets [abstract] | |||
| Financial assets at fair value through profit or loss [abstract] | |||
| Financial assets at fair value through profit or loss, designated upon initial recognition or subsequently | 
                                                6  791
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                6  383
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Cash and cash equivalents [abstract] | |||
| Cash and cash equivalents | 
                                                120,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                288,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                576,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
| Non-current portion of non-current borrowings, by type [abstract] | |||
| Non-current portion of non-current bonds issued | 
                                                19  558
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                19  558
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Current borrowings and current portion of non-current borrowings, by type [abstract] | |||
| Current loans received and current portion of non-current loans received | 
                                                12  597
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                12  595
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Current bonds issued and current portion of non-current bonds issued | 
                                                94,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                126,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Trade and other payables [abstract] | |||
| Other payables | 
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                1,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Issued capital [abstract] | |||
| Issued capital | 
                                                736,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                736,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Retained earnings [abstract] | |||
| Retained earnings | 
                                                9  072
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                8  655
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Accumulated other comprehensive income [abstract] | |||
| Revaluation surplus | 
                                                1  607
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                1  462
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Net assets (liabilities) [abstract] | |||
| Assets | 
                                                73 585
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                72 578
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Liabilities | 
                                                45 394
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                44 966
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Net current assets (liabilities) [abstract] | |||
| Current assets | 
                                                46 935
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                46 490
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Current liabilities | 
                                                25 324
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | 
                                                24 987
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             | — | 
| Assets less current liabilities [abstract] |