Key Financial Data Of Reporting Company
| 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 reporting company | ||||||
| Business results of reporting company | ||||||
| Net sales | — | 
                                                29,788,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                64,231,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                30,578,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                1,358,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,753,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,437,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                35,715,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                34,568,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                33,396,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                86,249,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                85,844,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                89,185,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                79.18
                                                
                                             | 
                                                128.10
                                                
                                             | — | — | 
                                                63.85
                                                
                                             | 
| Diluted earnings per share | — |  |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.414
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.403
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.373
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                1,151,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,432,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,200,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -614,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -301,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                314,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -116,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,966,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,396,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                5,768,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                4,939,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,329,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |