Key Financial Data Of Group
| Concept | As at 2024-03-31 | 2024-01-01 to 2024-03-31 | 2023-01-01 to 2023-12-31 | As at 2023-12-31 | 2023-01-01 to 2023-03-31 | As at 2023-03-31 | 
|---|---|---|---|---|---|---|
| Key financial data of group | ||||||
| Business results of group | ||||||
| Net sales | — | 
                                                1,370,964,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,219,251,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,252,596,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | 
                                                18,601,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                357,490,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -42,237,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) attributable to owners of parent | — | 
                                                -80,667,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -204,941,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -70,449,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Comprehensive income | — | 
                                                18,339,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                285,678,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -71,408,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | 
                                                1,189,845,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,744,943,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                807,796,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | 
                                                4,114,603,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                4,974,509,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,675,940,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Basic earnings (loss) per share | — | 
                                                -8.01
                                                
                                             | 
                                                -20.47
                                                
                                             | — | 
                                                -7.13
                                                
                                             | — | 
| Diluted earnings per share | — |  |  | — |  | — | 
| Equity-to-asset ratio | 
                                                0.211
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.191
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.217
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |