Employees
| Concept | As at 2024-08-31 | As at 2024-08-31 | As at 2024-08-31 | As at 2024-08-31 | As at 2024-08-31 | As at 2023-08-31 | As at 2022-08-31 | As at 2021-08-31 | As at 2020-08-31 | 
|---|---|---|---|---|---|---|---|---|---|
| Employees | |||||||||
| Information about reporting company | |||||||||
| Information about employees of reporting company | |||||||||
| Number of employees | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                112
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                24
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                136
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                138
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                135
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                126
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                119
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | — | 
                                                11
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                16
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                17
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                18
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                20
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                20
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average age (Years) | — | — | — | — | 
                                                41.6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
| Average length of service (Years) | — | — | — | — | 
                                                16.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
| Average annual salary | — | — | — | — | 
                                                5,886,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — |