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 | — | 
                                                29,815,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                67,947,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                33,424,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                602,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,947,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,660,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                32,716,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                33,269,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                32,382,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                56,787,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                55,247,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                53,942,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                29.75
                                                
                                             | 
                                                131.99
                                                
                                             | — | — | 
                                                75.75
                                                
                                             | 
| Diluted earnings per share | — |  |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.568
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.594
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.592
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                2,368,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,065,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                317,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -3,053,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,626,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,084,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -2,519,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,256,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,591,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                7,750,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,954,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,380,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |