Key Financial Data Of Reporting Company
| 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 reporting company | ||||||
| Business results of reporting company | ||||||
| Net sales | — | 
                                                1,506,432,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,639,951,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,117,759,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                -133,777,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -345,871,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -345,050,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                658,468,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                816,143,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                888,089,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                2,255,131,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,558,060,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,630,983,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                -24.82
                                                
                                             | 
                                                -123.17
                                                
                                             | — | — | 
                                                -109.70
                                                
                                             | 
| Diluted earnings per share | — |  |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.289
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.316
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.335
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                131,944,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -316,739,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -407,710,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -164,696,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -353,437,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -146,183,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -173,794,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                772,620,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                671,166,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                505,233,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                711,780,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                726,608,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |