Analysis Of Income And Expense [Abstract]
| Concept | 
                                    
                                        2021-01-01 to 2021-12-31  | 
                            
                                
                                    
                                        2020-01-01 to 2020-12-31  | 
                            
                        
|---|---|---|
| Analysis of income and expense [abstract] | ||
| Revenue [abstract] | ||
| Revenue | 
                                        
                                             
                                                434,970,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                373,709,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Material income and expense [abstract] | ||
| Impairment loss (reversal of impairment loss) on trade receivables [abstract] | ||
| Impairment loss (reversal of impairment loss) recognised in profit or loss, trade receivables | 
                                        
                                             
                                                125,663,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                98,707,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Interest expense | 
                                        
                                             
                                                51,845,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                64,185,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Interest income (expense) | 
                                        
                                             
                                                282,465,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                249,678,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Other operating income (expense) | 
                                        
                                             
                                                13,258,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                12,308,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Fee and commission income (expense) [abstract] | ||
| Fee and commission income [abstract] | ||
| Fee and commission income | 
                                        
                                             
                                                149,209,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                120,807,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Fee and commission expense [abstract] | ||
| Fee and commission expense | 
                                        
                                             
                                                25,704,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                21,615,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Fee and commission income (expense) | 
                                        
                                             
                                                123,505,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                99,192,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Comprehensive income, continuing and discontinued operations [abstract] | ||
| Comprehensive income | 
                                        
                                             
                                                103,422,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                45,401,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Comprehensive income attributable to owners of parent, continuing and discontinued operations [abstract] | ||
| Comprehensive income, attributable to owners of parent | 
                                        
                                             
                                                102,609,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                44,858,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Comprehensive income attributable to non-controlling interests, continuing and discontinued operations [abstract] | ||
| Comprehensive income, attributable to non-controlling interests | 
                                        
                                             
                                                813,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                543,000
                                                
                                                    
                                                        BGN
                                                    
                                                
                                             
                                        
                                     |