Key Financial Data Of Group
| Concept | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | 2023-10-01 to 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | 2023-10-01 to 2024-09-30 | As at 2023-09-30 | 2022-10-01 to 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 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Key financial data of group | |||||||||||||||||||||||
| Business results of group | |||||||||||||||||||||||
| Net sales | — | — | — | — | — | — | 
                                                89,782,840,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                86,085,923,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                79,143,550,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                66,121,899,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                65,338,446,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Operating revenue | — | — | — | 
                                                2,571,515,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                1,523,359,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,292,609,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                1,245,155,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,534,268,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Ordinary profit (loss) | — | — | — | 
                                                1,318,423,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,477,857,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                275,126,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,068,394,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                318,587,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,167,928,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                438,320,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,121,333,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                790,800,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,056,539,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Profit (loss) attributable to owners of parent | — | — | — | — | — | — | 
                                                1,268,949,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,274,131,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,647,329,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,309,968,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,348,925,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Comprehensive income | — | — | — | — | — | — | 
                                                1,298,078,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,537,189,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,432,226,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,575,301,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,338,159,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                24,863,332,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                11,238,570,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,561,569,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                24,179,517,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,636,882,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                23,209,140,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                10,782,095,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                22,199,410,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,655,598,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,052,070,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                44,961,550,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                20,278,565,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                18,583,678,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                44,002,545,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                16,752,260,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                42,640,134,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                17,178,479,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                36,921,787,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,768,805,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                34,343,494,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets per share | 
                                                1,074.87
                                                
                                             | — | — | — | 
                                                485.86
                                                
                                             | — | — | 
                                                456.59
                                                
                                             | — | 
                                                1,045.30
                                                
                                             | — | — | 
                                                459.84
                                                
                                             | 
                                                1,003.35
                                                
                                             | — | 
                                                466.12
                                                
                                             | — | 
                                                959.69
                                                
                                             | — | — | 
                                                460.65
                                                
                                             | 
                                                910.09
                                                
                                             | — | 
| Basic earnings (loss) per share | — | — | — | 
                                                51.63
                                                
                                             | — | — | 
                                                54.86
                                                
                                             | — | 
                                                15.27
                                                
                                             | — | 
                                                55.08
                                                
                                             | 
                                                16.65
                                                
                                             | — | — | 
                                                71.22
                                                
                                             | — | 
                                                20.22
                                                
                                             | — | 
                                                56.63
                                                
                                             | 
                                                36.09
                                                
                                             | — | — | 
                                                58.31
                                                
                                             | 
| Diluted earnings per share | — | — | — |  | — | — |  | — |  | — |  |  | — | — |  | — |  | — |  |  | — | — |  | 
| Equity-to-asset ratio | 
                                                0.553
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.554
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.568
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.550
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.635
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.544
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.628
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.601
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.989
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.613
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Rate of return on equity | — | — | — | 
                                                0.110
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.052
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.033
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.054
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.036
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.073
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.044
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.061
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.080
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.065
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Price-earnings ratio | — | — | — | 
                                                12.0
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                11.3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                41.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                11.6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                27.0
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                6.3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                25.3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                9.0
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                12.6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                7.8
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Net cash provided by (used in) operating activities | — | — | — | — | — | — | 
                                                2,825,025,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,677,487,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                395,989,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,941,595,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,310,939,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | — | — | — | — | — | 
                                                -641,735,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -2,876,869,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                388,431,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -364,197,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -127,124,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | — | — | — | — | — | 
                                                -640,082,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -811,465,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -1,457,139,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -256,402,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -653,998,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                12,184,132,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                10,166,176,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                12,113,433,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                12,780,376,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                11,459,381,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Number of employees | 
                                                1,148
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                124
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                923
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                28
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                101
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                30
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1,088
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                23
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,013
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                17
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                852
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                16
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                848
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Average number of temporary employees | 
                                                280
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                24
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                225
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                11
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                31
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                13
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                290
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                14
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                274
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                10
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                222
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                248
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — |