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 | — | 
                                                237,342,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                505,981,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                271,695,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                17,312,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -5,461,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                14,122,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                7,915,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                6,077,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                30,849,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                438,539,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                426,967,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                398,722,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                50.60
                                                
                                             | 
                                                -69.22
                                                
                                             | — | — | 
                                                29.28
                                                
                                             | 
| Diluted earnings per share | — | 
                                                13.85
                                                
                                             |  | — | — | 
                                                8.62
                                                
                                             | 
| Equity-to-asset ratio | 
                                                0.015
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.011
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.077
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                19,651,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                62,747,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                22,847,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -1,722,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,567,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,549,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -133,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -5,851,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -5,154,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                192,729,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                166,208,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                127,788,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |