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 | — | 
                                                12,183,230,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                23,739,835,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                11,917,444,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                199,372,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                82,483,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                99,812,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                3,180,208,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,070,641,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,765,684,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                7,283,575,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                7,174,136,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,003,284,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                15.91
                                                
                                             | 
                                                -142.75
                                                
                                             | — | — | 
                                                -1.11
                                                
                                             | 
| Diluted earnings per share | — | 
                                                15.91
                                                
                                             |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.400
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.392
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.480
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                -137,042,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,827,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -76,094,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -8,359,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                317,149,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -17,655,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -247,551,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -330,211,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -198,567,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                3,364,588,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,749,726,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,471,320,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |