Shareholdings
| Concept | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Shareholdings | ||||||||||||||
| Reporting company | ||||||||||||||
| Details of specified investment shares held for purposes other than pure investment | ||||||||||||||
| Issue | 
                                                ダイハツディーゼル㈱(注2)
                                                
                                             | 
                                                水道機工㈱
                                                
                                             | 
                                                ㈱三菱UFJフィナンシャル・グループ
                                                
                                             | 
                                                東海カーボン㈱
                                                
                                             | 
                                                MS&ADインシュアランスグループホールディングス㈱
                                                
                                             | 
                                                ㈱鶴見製作所
                                                
                                             | 
                                                ㈱明電舎
                                                
                                             | — | — | — | — | — | — | — | 
| Number of shares | 
                                                55,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                93,400
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                906,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                70,150
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                17,100
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                160,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                54,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                70,150
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                54,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                906,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                160,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                17,100
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                55,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
                                                93,400
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
| Carrying amount | 
                                                94,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                166,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,821,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                66,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                55,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                496,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                233,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                69,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                158,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,410,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                599,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                46,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                82,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                148,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Purpose of shareholding, overview of business alliance, quantitative effects of shareholding and reason for increase in number of shares | 
                                                事業活動の円滑な推進(注1)
                                                
                                             | 
                                                事業活動の円滑な推進(注1)
                                                
                                             | 
                                                事業活動の円滑な推進(注1)
                                                
                                             | 
                                                事業活動の円滑な推進(注1)
                                                
                                             | 
                                                事業活動の円滑な推進(注1)
                                                
                                             | 
                                                事業活動の円滑な推進(注1)
                                                
                                             | 
                                                事業活動の円滑な推進(注1)
                                                
                                             | — | — | — | — | — | — | — | 
| Whether issuer of aforementioned shares holds reporting company's shares | 
                                                有
                                                
                                             | 
                                                有
                                                
                                             | 
                                                有
                                                
                                             | 
                                                有
                                                
                                             | 
                                                無
                                                
                                             | 
                                                有
                                                
                                             | 
                                                有
                                                
                                             | — | — | — | — | — | — | — |