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 | 
                                                87,267,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                113,270,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                80,707,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | 
                                                5,053,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                5,827,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                5,336,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | — | 
                                                126,576,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                125,461,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                126,788,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Total assets | — | 
                                                178,942,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                176,045,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                174,562,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Basic earnings (loss) per share | 
                                                68.23
                                                
                                             | — | 
                                                37.55
                                                
                                             | — | 
                                                82.44
                                                
                                             | — | 
                                                76.40
                                                
                                             | 
                                                54.71
                                                
                                             | 
| Diluted earnings per share |  | — | — | — |  | — |  | — | 
| Equity-to-asset ratio | — | 
                                                0.707
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.713
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.726
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — |