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 | — | 
                                                7,651,326,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                14,078,418,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                6,835,783,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                906,023,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,485,161,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                739,172,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Profit (loss) attributable to owners of parent | — | 
                                                596,752,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                979,153,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                481,694,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Comprehensive income | — | 
                                                835,003,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                930,259,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                382,103,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                7,764,477,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                7,290,751,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,919,738,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                10,314,775,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,201,198,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,387,117,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                64.41
                                                
                                             | 
                                                105.09
                                                
                                             | — | — | 
                                                51.70
                                                
                                             | 
| Diluted earnings per share | — | 
                                                63.45
                                                
                                             | 
                                                103.70
                                                
                                             | — | — | 
                                                51.06
                                                
                                             | 
| Equity-to-asset ratio | 
                                                0.736
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.701
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.722
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                -72,253,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                804,956,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                392,959,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -103,138,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -71,407,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -34,585,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -404,126,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -364,958,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -187,454,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                3,180,336,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,759,855,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,562,185,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |