Shareholdings
| Concept | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | 
|---|---|---|
| Shareholdings | ||
| Reporting company | ||
| Investment shares held for purposes other than pure investment | ||
| Shares not listed | ||
| Number of issues | 
                                                8
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Carrying amount | 
                                                450,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Shares other than those not listed | ||
| Number of issues | 
                                                6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Carrying amount | 
                                                7,862,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Number of issues whose number of shares decreased | — | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Total sale amount for decreased shares | — | 
                                                1,389,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |