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 | — | — | 
                                                47,274,667,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                91,574,995,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                44,942,104,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | — | 
                                                1,050,046,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,516,614,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                891,641,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                15,035,749,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                14,716,291,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                13,835,212,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Total assets | 
                                                50,859,915,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                48,694,862,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                47,115,932,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Basic earnings (loss) per share | — | 
                                                34.58
                                                
                                             | 
                                                55.44
                                                
                                             | — | 
                                                133.51
                                                
                                             | — | 
                                                16.64
                                                
                                             | 
                                                51.53
                                                
                                             | 
| Equity-to-asset ratio | 
                                                0.296
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.302
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.294
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                2,456,351,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,527,484,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                458,008,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | — | 
                                                -418,782,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -1,029,536,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -527,098,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | — | 
                                                704,660,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -114,845,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,584,682,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                29,923,966,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                27,169,621,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                26,999,335,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — |