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 | — | 
                                                10,078,223,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,142,218,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,157,244,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                750,008,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,042,398,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                935,835,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Profit (loss) attributable to owners of parent | — | 
                                                608,160,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,740,081,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                929,798,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Comprehensive income | — | 
                                                974,695,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,948,132,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,170,078,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                18,278,533,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                17,564,049,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,810,977,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                24,541,599,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                24,629,028,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                23,735,473,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                76.95
                                                
                                             | 
                                                220.24
                                                
                                             | — | — | 
                                                117.69
                                                
                                             | 
| Diluted earnings per share | — | 
                                                76.36
                                                
                                             | 
                                                218.41
                                                
                                             | — | — | 
                                                116.63
                                                
                                             | 
| Equity-to-asset ratio | 
                                                0.731
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.700
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.695
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                820,036,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,431,533,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                561,340,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -327,990,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,616,747,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,550,348,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -594,656,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,067,082,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,265,814,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                3,136,859,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,213,159,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,603,626,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |