Shareholdings
| Concept | As at 2024-12-31 | As at 2023-12-31 | 
|---|---|---|
| Shareholdings | ||
| Largest holding company | ||
| Investment shares held for pure investment | ||
| Shares not listed | ||
| Number of issues | 
                                                15
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                18
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Carrying amount | 
                                                234,244,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                242,585,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shares other than those not listed | ||
| Number of issues | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Carrying amount | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |