Shareholdings
| Concept | 
                                    
                                        As at 2025-03-31  | 
                            
                                
                                    
                                        As at 2025-03-31  | 
                            
                        
|---|---|---|
| Shareholdings | ||
| Reporting company | ||
| Investment shares reclassified from held for purposes other than pure investment to held for pure investment | ||
| Issue | 
                                        
                                             
                                                株式会社佐賀銀行
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                株式会社ふくおかフィナンシャルグループ
                                                
                                             
                                        
                                     | 
                                
                            
| Number of shares | 
                                        
                                             
                                                135,691
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                86,648
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Carrying amount | 
                                        
                                             
                                                313,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                340,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             
                                        
                                     |