Employees
| Concept | As at 2025-02-28 | As at 2025-02-28 | As at 2024-05-15 | As at 2024-05-15 | As at 2023-05-15 | As at 2023-05-15 | As at 2022-05-15 | As at 2022-05-15 | As at 2021-05-15 | As at 2021-05-15 | 
|---|---|---|---|---|---|---|---|---|---|---|
| Employees | ||||||||||
| Information about reporting company | ||||||||||
| Information about employees of reporting company | ||||||||||
| Number of employees | 
                                                209
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                11,298
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                192
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                11,620
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                11,298
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                181
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                11,169
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                204
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                10,810
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                278
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                2
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                21,333
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                20,807
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                20,069
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                19,857
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                19,239
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average age (Years) | 
                                                46
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
| Average age (Months) | 
                                                3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
| Average length of service (Years) | 
                                                20
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
| Average length of service (Months) | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
| Average annual salary | 
                                                6,043,342
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — |