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 | — | — | 
                                                54,937,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                113,270,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                49,093,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | — | 
                                                1,387,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                5,827,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,171,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                126,226,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                125,461,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                124,735,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Total assets | 
                                                176,175,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                176,045,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                175,461,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Basic earnings (loss) per share | — | 
                                                18.85
                                                
                                             | 
                                                30.66
                                                
                                             | — | 
                                                82.44
                                                
                                             | — | 
                                                1.04
                                                
                                             | 
                                                21.69
                                                
                                             | 
| Diluted earnings per share | — | — |  | — |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.716
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.713
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.711
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                8,364,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,008,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                6,218,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | — | 
                                                327,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -6,275,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -3,707,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | — | 
                                                -2,020,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -3,363,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,030,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                25,584,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                18,816,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                27,001,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — |