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 | — | 
                                                30,281,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                51,496,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                25,169,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                -321,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,692,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -834,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Profit (loss) attributable to owners of parent | — | 
                                                -1,068,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -11,816,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -681,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Comprehensive income | — | 
                                                -2,328,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -8,127,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,230,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                26,735,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                29,351,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                39,014,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                61,557,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                60,447,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                65,912,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                -35.47
                                                
                                             | 
                                                -392.69
                                                
                                             | — | — | 
                                                -22.66
                                                
                                             | 
| Diluted earnings per share | — |  |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.434
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.486
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.592
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                -1,397,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                678,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                869,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                2,272,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -4,320,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,617,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -103,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,875,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                932,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                8,641,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                7,387,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,144,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |