Employees
| Concept | 
                                    
                                        As at 2025-03-31  | 
                            
                        
|---|---|
| Employees | |
| Metrics related to human capital diversity | |
| Metrics of reporting company | |
| Ratio of female employees in managerial positions | 
                                        
                                             
                                                0.037
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Ratio of male employees taking childcare leave | |
| Calculated based on provisions of article 71-4 item (1) of ordinance for enforcement of Act on Childcare Leave, Caregiver Leave, and Other Measures for the Welfare of Workers Caring for Children or Other Family Members | |
| All employees | 
                                        
                                             
                                                0.214
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Differences in wages between male and female employees | |
| All employees | 
                                        
                                             
                                                0.520
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Regular employees | 
                                        
                                             
                                                0.632
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Non-regular employees | 
                                        
                                             
                                                0.557
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     |