Key Financial Data Of Group
| Concept | 2023-04-01 to 2023-09-30 | As at 2023-09-30 | 2023-07-01 to 2023-09-30 | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | 
|---|---|---|---|---|---|
| Key financial data of group | |||||
| Business results of group | |||||
| Net sales | 
                                                11,772,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                38,278,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | 
                                                -328,071,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -450,418,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | — | 
                                                6,186,665,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,453,623,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | — | 
                                                6,410,574,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,587,417,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | 
                                                -47.93
                                                
                                             | — | 
                                                -41.08
                                                
                                             | — | 
                                                -79.90
                                                
                                             | 
| Diluted earnings per share |  | — | — | — |  | 
| Equity-to-asset ratio | — | 
                                                0.964
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.958
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | 
                                                -156,465,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -401,612,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | 
                                                -5,502,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -8,968,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | 
                                                3,023,992,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                10,694,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | — | 
                                                5,803,921,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,941,896,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |