Key Financial Data Of Reporting Company
| Concept | 2024-01-01 to 2024-03-31 | As at 2024-03-31 | 2023-01-01 to 2023-12-31 | As at 2023-12-31 | 2023-01-01 to 2023-03-31 | As at 2023-03-31 | 
|---|---|---|---|---|---|---|
| Key financial data of reporting company | ||||||
| Business results of reporting company | ||||||
| Net sales | 
                                                3,431,352,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                11,397,375,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,365,116,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | 
                                                159,401,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                126,609,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                87,961,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | — | 
                                                2,836,498,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,767,312,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,790,678,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | 
                                                7,978,025,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                7,281,524,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                7,959,569,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Basic earnings (loss) per share | 
                                                10.67
                                                
                                             | — | 
                                                8.13
                                                
                                             | — | 
                                                4.09
                                                
                                             | — | 
| Diluted earnings per share | 
                                                10.60
                                                
                                             | — | 
                                                8.03
                                                
                                             | — | 
                                                4.02
                                                
                                             | — | 
| Equity-to-asset ratio | — | 
                                                0.349
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.373
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.343
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |