Key Financial Data Of Reporting Company
| Concept | As at 2024-10-20 | As at 2024-10-20 | As at 2024-10-20 | As at 2024-10-20 | As at 2024-10-20 | As at 2024-10-20 | As at 2024-10-20 | As at 2024-10-20 | 2023-10-21 to 2024-10-20 | As at 2024-10-20 | 2023-10-21 to 2024-10-20 | As at 2024-10-20 | 2022-10-21 to 2023-10-20 | 2022-10-21 to 2023-10-20 | As at 2023-10-20 | As at 2023-10-20 | As at 2022-10-20 | As at 2022-10-20 | 2021-10-21 to 2022-10-20 | 2021-10-21 to 2022-10-20 | 2020-10-21 to 2021-10-20 | 2020-10-21 to 2021-10-20 | As at 2021-10-20 | As at 2021-10-20 | 2019-10-21 to 2020-10-20 | As at 2020-10-20 | 2019-10-21 to 2020-10-20 | As at 2020-10-20 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Key financial data of reporting company | ||||||||||||||||||||||||||||
| Business results of reporting company | ||||||||||||||||||||||||||||
| Net sales | — | — | — | — | — | — | — | — | 
                                                3,284,567,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,342,957,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,881,579,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,795,941,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                2,797,805,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,764,338,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,630,420,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,601,637,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,908,719,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | — | — | — | — | — | — | — | 
                                                375,709,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                393,318,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                185,484,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                152,466,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                137,884,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                139,291,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                36,689,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                42,098,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                265,994,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) | — | — | — | — | — | — | — | — | 
                                                266,127,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                147,437,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                94,527,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                22,553,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                179,324,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Equity in earnings (losses) of affiliates if equity method is applied | — | — | — | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Share capital | — | — | — | — | — | 
                                                479,885,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                479,885,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                479,885,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                479,885,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                479,885,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Total number of issued shares | — | — | — | — | — | 
                                                5,969,024
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                5,969,024
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | 
                                                5,969,024
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | — | — | — | 
                                                5,969,024
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | 
                                                5,969,024
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | 
| Net assets | — | — | — | — | — | 
                                                3,248,217,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                3,293,650,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,994,873,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,026,892,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,855,784,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,849,684,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                2,655,840,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,647,286,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,642,848,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | — | — | — | — | 
                                                6,001,088,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                6,065,031,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                5,927,125,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,982,973,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,766,254,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,752,256,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                5,452,888,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,437,452,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                5,399,797,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | — | — | — | — | — | 
                                                579.99
                                                
                                             | — | — | — | — | — | 
                                                588.10
                                                
                                             | — | — | 
                                                534.76
                                                
                                             | 
                                                540.47
                                                
                                             | 
                                                509.92
                                                
                                             | 
                                                508.83
                                                
                                             | — | — | — | — | 
                                                474.22
                                                
                                             | 
                                                472.69
                                                
                                             | — | 
                                                471.90
                                                
                                             | — |  | 
| Dividend paid per share | — | — | — | — | — | — | — | — | 
                                                5.00
                                                
                                             | — | — | — | — | 
                                                5.00
                                                
                                             | — | — | — | — | — | 
                                                5.00
                                                
                                             | — | 
                                                5.00
                                                
                                             | — | — | — | — | 
                                                5.00
                                                
                                             | — | 
| Interim dividend paid per share | — | — | — | — | — | — | — | — |  | — | — | — | — |  | — | — | — | — | — |  | — |  | — | — | — | — |  | — | 
| Basic earnings (loss) per share | — | — | — | — | — | — | — | — | 
                                                47.52
                                                
                                             | — | 
                                                49.91
                                                
                                             | — | 
                                                30.95
                                                
                                             | 
                                                26.33
                                                
                                             | — | — | — | — | 
                                                16.17
                                                
                                             | 
                                                16.88
                                                
                                             | 
                                                5.56
                                                
                                             | 
                                                4.03
                                                
                                             | — | — |  | — | 
                                                32.02
                                                
                                             | — | 
| Diluted earnings per share | — | — | — | — | — | — | — | — |  | — |  | — |  |  | — | — | — | — |  |  |  |  | — | — |  | — |  | — | 
| Equity-to-asset ratio | — | — | — | — | — | 
                                                0.541
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                0.543
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.505
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.506
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.495
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.495
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                0.487
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.487
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.489
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | — | — | — | — | — | — | — | 
                                                0.082
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.085
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.057
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.049
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                0.033
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.034
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.012
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.009
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.070
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | — | — | — | — | — | — | — | — | 
                                                8.33
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                7.93
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                10.69
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                12.57
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                16.82
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                16.12
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                63.15
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                87.16
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                10.12
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Payout ratio | — | — | — | — | — | — | — | — | 
                                                0.105
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                0.190
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                0.296
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1.242
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                0.156
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | — | — | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                338,988,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                56,144,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -53,031,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                311,409,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                45,790,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | — | — | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -16,322,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -68,836,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -232,017,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -154,303,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -43,474,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | — | — | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -245,827,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -22,469,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                180,232,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -43,396,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -288,418,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                213,963,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                137,125,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                172,286,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                277,102,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                163,393,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Number of employees | 
                                                9
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                21
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                154
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                184
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                21
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                161
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                9
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                191
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                177
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                184
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                187
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                181
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                188
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                181
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                170
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Total shareholder return | — | — | — | — | — | 
                                                1.199
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.818
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                1.028
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.937
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
| Total return on share price index | — | — | — | — | — | 
                                                1.869
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                1.532
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                1.255
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                1.308
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1.027
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — |