Key Financial Data Of Group
| Concept | 2023-07-01 to 2023-12-31 | As at 2023-12-31 | 2023-10-01 to 2023-12-31 | As at 2023-06-30 | 2022-07-01 to 2023-06-30 | 
|---|---|---|---|---|---|
| Key financial data of group | |||||
| Business results of group | |||||
| Net sales | 
                                                638,478,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,353,869,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | 
                                                -17,215,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                204,135,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | — | 
                                                3,215,479,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,166,377,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | — | 
                                                3,579,949,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,576,114,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | 
                                                -3.16
                                                
                                             | — | 
                                                22.60
                                                
                                             | — | 
                                                62.85
                                                
                                             | 
| Diluted earnings per share |  | — | — | — |  | 
| Equity-to-asset ratio | — | 
                                                0.898
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.739
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | 
                                                -39,787,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                150,321,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | 
                                                -18,359,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -36,874,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | 
                                                2,008,511,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -60,100,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | — | 
                                                2,622,173,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                671,809,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |