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 | — | 
                                                11,595,711,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,651,665,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,983,958,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                817,409,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,248,704,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                600,488,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Profit (loss) attributable to owners of parent | — | 
                                                772,783,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                962,353,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                447,565,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Comprehensive income | — | 
                                                556,295,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,731,126,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,019,199,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                24,264,605,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                23,799,922,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                22,184,631,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                33,573,045,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                33,316,898,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                31,718,254,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                174.05
                                                
                                             | 
                                                216.74
                                                
                                             | — | — | 
                                                100.80
                                                
                                             | 
| Equity-to-asset ratio | 
                                                0.698
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.692
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.674
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                1,179,613,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                992,482,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                638,929,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -1,218,092,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -700,431,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -422,874,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -110,877,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -240,994,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -109,030,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                7,922,502,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                7,947,016,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,972,228,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |