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 | — | — | 
                                                51,860,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                105,709,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                52,404,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | — | 
                                                4,384,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                8,342,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,954,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                82,639,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                79,704,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                78,688,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Total assets | 
                                                101,616,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                98,188,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                97,113,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Basic earnings (loss) per share | — | 
                                                34.93
                                                
                                             | 
                                                85.86
                                                
                                             | — | 
                                                164.34
                                                
                                             | — | 
                                                30.78
                                                
                                             | 
                                                77.10
                                                
                                             | 
| Diluted earnings per share | — | — | 
                                                84.82
                                                
                                             | — |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.795
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.794
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.793
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                199,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                7,121,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,810,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | — | 
                                                -1,562,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -304,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -155,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | — | 
                                                -1,478,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -2,860,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,760,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                49,975,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                52,639,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                48,653,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — |