Key Financial Data Of Reporting Company
| Concept | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | 2022-10-01 to 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | 2022-10-01 to 2023-09-30 | 2021-10-01 to 2022-09-30 | As at 2022-09-30 | As at 2022-09-30 | 2021-10-01 to 2022-09-30 | As at 2021-09-30 | 2020-10-01 to 2021-09-30 | As at 2021-09-30 | 2020-10-01 to 2021-09-30 | 2019-10-01 to 2020-09-30 | As at 2020-09-30 | As at 2020-09-30 | 2019-10-01 to 2020-09-30 | 2018-10-01 to 2019-09-30 | As at 2019-09-30 | 2018-10-01 to 2019-09-30 | As at 2019-09-30 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Key financial data of reporting company | ||||||||||||||||||||||||||||||
| Business results of reporting company | ||||||||||||||||||||||||||||||
| Net sales | — | — | — | 
                                                4,214,862,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                7,577,563,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,515,194,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                7,220,655,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                4,438,634,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                6,985,957,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,908,670,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                6,122,590,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,419,509,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                6,149,550,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | — | — | 
                                                290,348,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                685,200,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                490,774,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                856,637,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                504,556,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                801,416,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                325,453,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                419,788,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                461,059,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                474,992,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) | — | — | — | 
                                                459,546,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | 
                                                259,787,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                357,473,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                191,542,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                323,084,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Share capital | 
                                                762,266,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                761,166,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                88,888,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                88,888,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                88,888,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total number of issued shares | 
                                                2,697,600
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                2,695,400
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | 
                                                2,000,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | — | — | 
                                                2,000,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | — | — | — | 
                                                20,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
| Net assets | 
                                                3,654,586,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                4,538,382,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                3,349,883,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,795,059,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,823,457,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,115,494,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,464,177,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,529,517,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,299,986,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,276,102,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | 
                                                5,150,380,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                8,373,744,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                4,581,933,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,487,369,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,709,251,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                6,020,954,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,483,956,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,081,066,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                5,815,210,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,985,052,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | 
                                                1,354.25
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                1,652.17
                                                
                                             | — | — | — | — | 
                                                1,242.81
                                                
                                             | 
                                                1,386.92
                                                
                                             | — | 
                                                911.73
                                                
                                             | — | 
                                                1,031.90
                                                
                                             | — | — | 
                                                732.09
                                                
                                             | 
                                                745.04
                                                
                                             | — | — | 
                                                633.62
                                                
                                             | — | 
                                                638.05
                                                
                                             | 
| Dividend paid per share | — | — | — | 
                                                51.00
                                                
                                             | — | — | — | — | — | — | — | — | — | — | 
                                                50.00
                                                
                                             | — | — | — | — | 
                                                25.00
                                                
                                             | — | — |  | — | — | — | 
                                                3,000.00
                                                
                                             | — | — | — | 
| Interim dividend paid per share | — | — | — | 
                                                25.00
                                                
                                             | — | — | — | — | — | — | — | — | — | — | 
                                                10.00
                                                
                                             | — | — | — | — |  | — | — |  | — | — | — |  | — | — | — | 
| Basic earnings (loss) per share | — | — | — | 
                                                170.45
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                324.40
                                                
                                             | 
                                                97.52
                                                
                                             | — | — | 
                                                153.17
                                                
                                             | — | 
                                                178.74
                                                
                                             | — | 
                                                285.95
                                                
                                             | 
                                                95.77
                                                
                                             | — | — | 
                                                113.16
                                                
                                             | 
                                                161.54
                                                
                                             | — | 
                                                118.09
                                                
                                             | — | 
| Diluted earnings per share | — | — | — | 
                                                167.91
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                319.56
                                                
                                             | 
                                                95.77
                                                
                                             | — | — | 
                                                150.42
                                                
                                             | — |  | — |  |  | — | — |  |  | — |  | — | 
| Equity-to-asset ratio | 
                                                0.709
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                0.532
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                0.731
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.576
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.492
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.343
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.420
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.245
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.218
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.428
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | — | — | 
                                                0.131
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                0.213
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.100
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.141
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.217
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.322
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.140
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.164
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.282
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.201
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | — | — | — | 
                                                10.4
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                5.5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                17.3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                11.0
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Payout ratio | — | — | — | 
                                                0.299
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | 
                                                0.513
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                0.140
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.186
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
| Net cash provided by (used in) operating activities | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                766,021,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                884,125,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,475,148,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                549,742,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                251,787,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                418,341,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -743,190,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -170,814,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -800,544,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,314,498,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                -425,334,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                263,014,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -1,165,807,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                94,255,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,051,057,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | — | — | — | — | — | — | — | — | — | 
                                                1,854,553,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                1,095,525,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                691,539,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                552,995,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                709,541,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Number of employees | 
                                                151
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                30
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                30
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                14
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                71
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                15
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                15
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                21
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                97
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                274
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                21
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                111
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                143
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                213
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                138
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                190
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                128
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                179
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                176
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                124
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                53
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                38
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                84
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                235
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                137
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                46
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                208
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                106
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                269
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                75
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                198
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                143
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                49
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Total shareholder return | 
                                                1.088
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Total return on share price index | 
                                                1.298
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |