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 | — | — | 
                                                31,648,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                60,461,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                30,172,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | — | 
                                                3,096,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                5,232,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,987,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                58,621,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                54,533,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                52,002,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Total assets | 
                                                91,920,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                87,138,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                86,227,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Basic earnings (loss) per share | — | 
                                                95.41
                                                
                                             | 
                                                145.93
                                                
                                             | — | 
                                                150.08
                                                
                                             | — | 
                                                36.25
                                                
                                             | 
                                                83.18
                                                
                                             | 
| Diluted earnings per share | — | — |  | — |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.638
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.626
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.603
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                3,097,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,351,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,666,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | — | 
                                                1,382,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -1,126,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -199,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | — | 
                                                -2,539,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -1,820,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,346,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                19,446,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                17,505,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                17,224,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — |