Key Financial Data Of Reporting Company
| Concept | 2023-04-01 to 2023-12-31 | As at 2023-12-31 | 2023-10-01 to 2023-12-31 | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | As at 2022-12-31 | 2022-04-01 to 2022-12-31 | 2022-10-01 to 2022-12-31 | 
|---|---|---|---|---|---|---|---|---|
| Key financial data of reporting company | ||||||||
| Business results of reporting company | ||||||||
| Net sales | 
                                                48,824,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                60,461,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                47,259,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | 
                                                5,631,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                5,232,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                5,246,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | — | 
                                                60,391,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                54,533,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                54,080,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Total assets | — | 
                                                94,857,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                87,138,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                90,794,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Basic earnings (loss) per share | 
                                                228.13
                                                
                                             | — | 
                                                82.19
                                                
                                             | — | 
                                                150.08
                                                
                                             | — | 
                                                148.19
                                                
                                             | 
                                                64.97
                                                
                                             | 
| Diluted earnings per share |  | — | — | — |  | — |  | — | 
| Equity-to-asset ratio | — | 
                                                0.637
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.626
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.596
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — |