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 | — | 
                                                87,764,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                171,345,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                86,618,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                20,607,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                35,317,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                18,494,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                329,038,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                316,230,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                298,944,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                427,040,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                411,406,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                393,016,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Basic earnings (loss) per share | — | 
                                                122.64
                                                
                                             | 
                                                225.68
                                                
                                             | — | — | 
                                                115.38
                                                
                                             | 
| Diluted earnings per share | — |  |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.576
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.575
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.570
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                20,003,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                22,076,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                9,438,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | 
                                                -8,252,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -9,805,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                94,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | 
                                                -4,404,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -7,542,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -5,231,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                83,923,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                77,929,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                77,070,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — |