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 | — | 
                                                55,139,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                119,532,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                54,937,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                2,050,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,822,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,578,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                130,027,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                130,735,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                126,158,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                178,865,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                177,627,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                176,102,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                21.86
                                                
                                             | 
                                                95.41
                                                
                                             | — | — | 
                                                32.97
                                                
                                             | 
| Diluted earnings per share | — |  |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.727
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.736
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.716
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                3,379,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,549,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                8,364,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -5,235,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,187,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                327,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                1,987,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,347,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,020,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                14,017,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                13,886,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                25,584,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |