Key Financial Data Of Group
| Concept | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | As at 2025-03-31 | 2023-04-01 to 2024-03-31 | 2023-04-01 to 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | 2022-04-01 to 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | 2021-04-01 to 2022-03-31 | 2021-04-01 to 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2021-03-31 | 2020-04-01 to 2021-03-31 | 2020-04-01 to 2021-03-31 | As at 2021-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Key financial data of group | ||||||||||||||||||||||||||||
| Business results of group | ||||||||||||||||||||||||||||
| Net sales | — | — | — | — | — | — | — | 
                                                990,407,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                620,534,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                596,779,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                964,090,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                580,801,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                933,114,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                497,157,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                802,854,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                435,334,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                718,013,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | — | — | — | — | — | — | 
                                                30,521,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,735,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                23,473,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                24,809,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -8,113,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                34,940,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                14,433,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                40,286,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -10,539,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                13,227,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) attributable to owners of parent | — | — | — | — | — | — | — | 
                                                37,837,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -29,814,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                11,470,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                22,960,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -3,837,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Comprehensive income | — | — | — | — | — | — | — | 
                                                31,490,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                1,485,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                19,805,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                52,258,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                23,725,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | — | — | — | — | — | — | 
                                                415,515,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                192,783,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                392,824,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                158,406,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                151,368,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                399,782,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                425,308,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                169,597,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                378,379,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                159,836,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | — | — | — | — | — | 
                                                740,715,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                431,347,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                753,989,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                423,208,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                409,262,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                736,997,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                743,520,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                397,814,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                694,285,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                388,108,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | — | — | — | — | — | — | 
                                                2,013.07
                                                
                                             | — | — | 
                                                937.39
                                                
                                             | — | — | — | — | 
                                                1,902.43
                                                
                                             | 
                                                770.19
                                                
                                             | — | 
                                                736.15
                                                
                                             | 
                                                1,937.47
                                                
                                             | — | — | — | 
                                                1,879.42
                                                
                                             | 
                                                817.88
                                                
                                             | 
                                                1,665.29
                                                
                                             | — | — | 
                                                770.93
                                                
                                             | 
| Basic earnings (loss) per share | — | — | — | — | — | — | — | 
                                                184.00
                                                
                                             | — | — | 
                                                211.35
                                                
                                             | — | 
                                                66.39
                                                
                                             | 
                                                -145.04
                                                
                                             | — | — | 
                                                -54.07
                                                
                                             | — | — | 
                                                55.77
                                                
                                             | 
                                                70.97
                                                
                                             | 
                                                110.82
                                                
                                             | — | — | — | 
                                                -63.52
                                                
                                             | 
                                                -18.72
                                                
                                             | — | 
| Diluted earnings per share | — | — | — | — | — | — | — | 
                                                184.00
                                                
                                             | — | — | 
                                                211.34
                                                
                                             | — | 
                                                66.38
                                                
                                             |  | — | — |  | — | — | 
                                                55.76
                                                
                                             | 
                                                70.95
                                                
                                             | 
                                                110.79
                                                
                                             | — | — | — |  |  | — | 
| Equity-to-asset ratio | — | — | — | — | — | — | 
                                                0.559
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.447
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                0.519
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.374
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.370
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.540
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.524
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.426
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.497
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.411
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | — | — | — | — | — | — | 
                                                0.094
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.248
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.088
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                -0.076
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                -0.069
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.029
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.089
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.063
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                -0.078
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                -0.011
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | — | — | — | — | — | — | — | 
                                                8.3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                7.2
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                18.0
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                22.8
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                17.1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                10.9
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | — | — | — | — | — | — | 
                                                65,817,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                89,173,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                15,413,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                34,304,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                42,636,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | — | — | — | — | — | — | 
                                                -1,683,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -55,095,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -54,205,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -45,507,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -41,165,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | — | — | — | — | — | — | 
                                                -37,299,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -1,808,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -742,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -13,539,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                14,515,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | — | — | — | — | — | 
                                                147,464,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | 
                                                122,298,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                82,893,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                138,489,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                151,748,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Number of employees | 
                                                2,864
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                13,686
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,392
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,261
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2,173
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8,811
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                27,287
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1,529
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                6,429
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                28,693
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                6,597
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                6,784
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                29,926
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                36,900
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                6,989
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                38,471
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                7,133
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                413
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,302
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                211
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                257
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                323
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                372
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2,239
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                947
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                308
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                2,229
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                828
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                681
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,788
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                4,937
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                597
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                5,211
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                501
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |