Key Financial Data Of Reporting Company
| Concept | As at 2023-09-30 | 2023-07-01 to 2023-09-30 | 2023-04-01 to 2023-09-30 | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | As at 2022-09-30 | 2022-07-01 to 2022-09-30 | 2022-04-01 to 2022-09-30 | 
|---|---|---|---|---|---|---|---|---|
| Key financial data of reporting company | ||||||||
| Business results of reporting company | ||||||||
| Net sales | — | — | 
                                                365,516,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                794,621,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                293,166,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | — | 
                                                30,639,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -149,503,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -129,668,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                1,105,478,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,078,616,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,232,179,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Total assets | 
                                                1,434,394,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,434,337,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,561,617,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Basic earnings (loss) per share | — | 
                                                1.68
                                                
                                             | 
                                                2.88
                                                
                                             | — | 
                                                -31.10
                                                
                                             | — | 
                                                -8.29
                                                
                                             | 
                                                -14.62
                                                
                                             | 
| Diluted earnings per share | — | — |  | — |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.771
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.752
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.789
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                7,081,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                26,458,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -50,626,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | — | 
                                                -8,821,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                30,036,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -63,950,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | — | 
                                                2,996,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                991,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,995,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                566,074,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                561,997,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                340,795,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — |