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 | — | 
                                                427,142,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,467,931,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                391,791,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | 
                                                20,563,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                50,575,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                23,688,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) | — | 
                                                19,993,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                52,589,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                22,406,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Equity in earnings (losses) of affiliates if equity method is applied | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Share capital | 
                                                213,128,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                213,128,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                212,928,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total number of issued shares | 
                                                1,440,600
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | 
                                                1,440,600
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | 
                                                720,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
| Net assets | 
                                                398,636,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                378,643,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                348,417,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | 
                                                593,465,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                595,703,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                590,415,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Dividend paid per share | — |  |  | — |  | — | 
| Basic earnings (loss) per share | — | 
                                                13.88
                                                
                                             | 
                                                36.51
                                                
                                             | — | 
                                                15.56
                                                
                                             | — | 
| Diluted earnings per share | — | 
                                                13.86
                                                
                                             | 
                                                36.43
                                                
                                             | — | 
                                                15.51
                                                
                                             | — | 
| Equity-to-asset ratio | 
                                                0.665
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.629
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.583
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |