Shareholdings
| Concept | As at 2024-10-20 | As at 2024-10-20 | As at 2024-10-20 | As at 2024-10-20 | As at 2023-10-20 | As at 2023-10-20 | As at 2023-10-20 | As at 2023-10-20 | 
|---|---|---|---|---|---|---|---|---|
| Shareholdings | ||||||||
| Reporting company | ||||||||
| Details of specified investment shares held for purposes other than pure investment | ||||||||
| Issue | 
                                                ㈱大光銀行
                                                
                                             | 
                                                ㈱BSNメディアホールディングス
                                                
                                             | 
                                                ㈱第四北越フィナンシャルグループ
                                                
                                             | 
                                                ㈱植木組
                                                
                                             | — | — | — | — | 
| Number of shares | 
                                                10,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                16,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                35,400
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                6,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                6,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                16,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                10,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                17,700
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
| Carrying amount | 
                                                13,320,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                26,880,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                87,579,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,144,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,496,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                24,928,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                14,820,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                67,083,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Purpose of shareholding, overview of business alliance, quantitative effects of shareholding and reason for increase in number of shares | 
                                                長期的・安定的な取引関係の維持のため(注)1
                                                
                                             | 
                                                長期的・安定的な取引関係の維持のため(注)1
                                                
                                             | 
                                                長期的・安定的な取引関係の維持のため(注)1
                                                
                                             | 
                                                長期的・安定的な取引関係の維持のため(注)1
                                                
                                             | — | — | — | — | 
| Whether issuer of aforementioned shares holds reporting company's shares | 
                                                有
                                                
                                             | 
                                                有
                                                
                                             | 
                                                無 (注)2
                                                
                                             | 
                                                有
                                                
                                             | — | — | — | — |