Key Financial Data Of Reporting Company
| Concept | As at 2024-05-31 | 2024-03-01 to 2024-05-31 | 2023-03-01 to 2024-02-29 | As at 2024-02-29 | 2023-03-01 to 2023-05-31 | As at 2023-05-31 | 
|---|---|---|---|---|---|---|
| Key financial data of reporting company | ||||||
| Business results of reporting company | ||||||
| Net sales | — | 
                                                474,589,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,205,457,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                571,686,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | 
                                                -45,696,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -371,162,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -78,624,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) | — | 
                                                -45,868,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,281,854,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -78,837,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Equity in earnings (losses) of affiliates if equity method is applied | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Share capital | 
                                                401,160,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                401,160,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                401,160,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total number of issued shares | 
                                                2,963,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | 
                                                2,963,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | 
                                                2,963,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
| Net assets | 
                                                1,431,560,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,477,429,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,680,476,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | 
                                                1,769,132,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,646,593,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,352,624,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Dividend paid per share | — |  |  | — |  | — | 
| Basic earnings (loss) per share | — | 
                                                -15.48
                                                
                                             | 
                                                -432.63
                                                
                                             | — | 
                                                -26.61
                                                
                                             | — | 
| Diluted earnings per share | — |  |  | — |  | — | 
| Equity-to-asset ratio | 
                                                0.809
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.897
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.800
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |