Key Financial Data Of Reporting Company
| Concept | As at 2023-09-30 | 2023-07-01 to 2023-09-30 | 2023-04-01 to 2023-09-30 | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | As at 2022-09-30 | 2022-07-01 to 2022-09-30 | 2022-04-01 to 2022-09-30 | 
|---|---|---|---|---|---|---|---|---|
| Key financial data of reporting company | ||||||||
| Business results of reporting company | ||||||||
| Net sales | — | — | 
                                                3,361,062,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                6,579,127,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,378,580,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | — | 
                                                274,553,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                431,759,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                213,047,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                2,261,305,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,068,761,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,821,686,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Total assets | 
                                                8,094,553,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                7,273,419,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                7,016,800,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Basic earnings (loss) per share | — | 
                                                66.21
                                                
                                             | 
                                                148.37
                                                
                                             | — | 
                                                298.08
                                                
                                             | — | 
                                                40.38
                                                
                                             | 
                                                103.60
                                                
                                             | 
| Diluted earnings per share | — | — |  | — |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.277
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.282
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.258
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                -330,761,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -115,329,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                62,154,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | — | 
                                                -86,959,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                201,034,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -70,893,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | — | 
                                                644,587,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -17,122,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                7,087,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                722,065,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                495,199,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                424,965,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — |