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 | — | 
                                                444,127,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                816,701,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                365,516,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                64,211,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                125,413,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                30,639,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Profit (loss) attributable to owners of parent | — | 
                                                71,512,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                186,694,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                26,861,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Comprehensive income | — | 
                                                71,512,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                186,694,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                26,861,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                1,336,823,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,265,311,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,105,478,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                1,645,596,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,618,582,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,434,394,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                7.68
                                                
                                             | 
                                                20.05
                                                
                                             | — | — | 
                                                2.88
                                                
                                             | 
| Diluted earnings per share | — |  |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.812
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.782
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.771
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                76,778,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                133,775,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                7,081,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -44,161,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -24,496,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -8,821,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -38,857,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                991,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,996,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                665,662,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                674,969,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                566,074,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |