Key Financial Data Of Group
| Concept | 2024-01-01 to 2024-06-30 | As at 2024-06-30 | 2023-01-01 to 2023-12-31 | As at 2023-12-31 | 2023-01-01 to 2023-06-30 | As at 2023-06-30 | 
|---|---|---|---|---|---|---|
| Key financial data of group | ||||||
| Business results of group | ||||||
| Net sales | 
                                                50,746,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                93,057,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                47,623,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | 
                                                6,853,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                10,153,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                7,287,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) attributable to owners of parent | 
                                                4,883,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                7,534,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                5,289,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Comprehensive income | 
                                                6,302,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                9,667,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                6,505,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | — | 
                                                59,391,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                55,093,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                51,851,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | 
                                                85,877,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                79,914,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                81,234,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Basic earnings (loss) per share | 
                                                352.10
                                                
                                             | — | 
                                                542.13
                                                
                                             | — | 
                                                379.67
                                                
                                             | — | 
| Diluted earnings per share |  | — |  | — |  | — | 
| Equity-to-asset ratio | — | 
                                                0.689
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.687
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.636
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Net cash provided by (used in) operating activities | 
                                                15,362,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                874,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                16,421,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | 
                                                -519,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -912,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -347,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | 
                                                -1,995,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -3,291,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -3,206,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | 
                                                32,943,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                19,654,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                35,923,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |