Key Financial Data Of Group
| Concept | As at 2024-09-30 | 2024-04-01 to 2024-09-30 | 2023-04-01 to 2024-03-31 | As at 2024-03-31 | As at 2023-09-30 | 2023-04-01 to 2023-09-30 | 
|---|---|---|---|---|---|---|
| Key financial data of group | ||||||
| Business results of group | ||||||
| Net sales | — | 
                                                4,546,940,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,232,639,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                4,209,057,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                -229,559,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                219,359,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -17,786,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Profit (loss) attributable to owners of parent | — | 
                                                -158,195,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                78,995,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -9,548,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Comprehensive income | — | 
                                                -145,091,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                108,075,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -5,927,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                931,257,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,063,036,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                947,153,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                5,691,826,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                5,380,884,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,272,389,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                -22.21
                                                
                                             | 
                                                11.12
                                                
                                             | — | — | 
                                                -1.35
                                                
                                             | 
| Diluted earnings per share | — |  | 
                                                10.79
                                                
                                             | — | — |  | 
| Equity-to-asset ratio | 
                                                0.158
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.192
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.174
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                -190,799,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                537,020,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                101,943,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -283,865,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -417,901,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -241,369,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                506,652,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                269,770,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                330,174,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                1,503,053,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,471,066,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,272,925,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |