Statement Of Cash Flows [Abstract]
| Concept | 
                                    
                                        As at 2022-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                                
                                    
                                        2022-01-01 to 2022-12-31  | 
                            
                                
                                    
                                        2021-01-01 to 2021-12-31  | 
                            
                                
                                    
                                        2021-01-01 to 2021-12-31  | 
                            
                                
                                    
                                        2021-01-01 to 2021-12-31  | 
                            
                                
                                    
                                        As at 2021-12-31  | 
                            
                                
                                    
                                        2021-01-01 to 2021-12-31  | 
                            
                                
                                    
                                        2021-01-01 to 2021-12-31  | 
                            
                                
                                    
                                        2021-01-01 to 2021-12-31  | 
                            
                                
                                    
                                        2021-01-01 to 2021-12-31  | 
                            
                                
                                    
                                        2021-01-01 to 2021-12-31  | 
                            
                                
                                    
                                        2021-01-01 to 2021-12-31  | 
                            
                                
                                    
                                        As at 2020-12-31  | 
                            
                        
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||||||||||||||||||
| Cash flows from (used in) operating activities [abstract] | |||||||||||||||||||||
| Profit (loss) | — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                97,990,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                97,241,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                749,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                813,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                -
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                111,408,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                110,595,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | 
| Adjustments to reconcile profit (loss) [abstract] | |||||||||||||||||||||
| Adjustments for income tax expense | — | — | 
                                        
                                             
                                                12,139,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                13,424,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Adjustments for impairment loss (reversal of impairment loss) recognised in profit or loss | — | — | 
                                        
                                             
                                                140,230,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                125,664,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Other adjustments for non-cash items | — | — | 
                                        
                                             
                                                535,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                5,835,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Adjustments for losses (gains) on disposal of non-current assets | — | — | 
                                        
                                             
                                                21,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                13,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Other adjustments to reconcile profit (loss) | — | — | 
                                        
                                             
                                                55,591,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                51,027,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Cash flows from (used in) operations | — | — | 
                                        
                                             
                                                47,104,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                44,286,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Interest paid, classified as operating activities | — | — | 
                                        
                                             
                                                60,197,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                72,731,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Interest received, classified as operating activities | — | — | 
                                        
                                             
                                                425,014,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                371,517,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Cash flows from (used in) operating activities | — | — | 
                                        
                                             
                                                1,950,474,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                138,359,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Cash flows from (used in) investing activities [abstract] | |||||||||||||||||||||
| Proceeds from sales of other long-term assets, classified as investing activities | — | — | 
                                        
                                             
                                                46,128,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                14,396,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Income taxes paid (refund), classified as investing activities | — | — | 
                                        
                                             
                                                8,333,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                5,039,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Cash flows from (used in) investing activities | — | — | 
                                        
                                             
                                                1,698,014,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                116,365,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Cash flows from (used in) financing activities [abstract] | |||||||||||||||||||||
| Cash flows from (used in) financing activities | — | — | 
                                        
                                             
                                                43,325,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                69,598,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Increase (decrease) in cash and cash equivalents after effect of exchange rate changes | — | — | 
                                        
                                             
                                                209,135,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                185,126,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | 
| Cash and cash equivalents | 
                                        
                                             
                                                2,226,780,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | — | — | — | — | — | — | 
                                        
                                             
                                                2,017,645,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    — | — | — | — | — | — | 
                                        
                                             
                                                2,202,771,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     |