Key Financial Data Of Group
| Concept | As at 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 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 | — | — | 
                                                456,969,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                268,883,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                243,866,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                505,981,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                221,153,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                430,163,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                177,743,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                311,115,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                136,323,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                315,393,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | — | 
                                                32,196,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                14,015,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                14,862,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -5,461,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                17,280,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                20,322,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,078,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                11,431,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                127,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,462,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) attributable to owners of parent | — | — | 
                                                26,987,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -15,831,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                15,187,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -12,629,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                7,993,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Comprehensive income | — | — | 
                                                19,451,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -16,287,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                6,794,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -17,272,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                11,847,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | — | 
                                                25,456,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,168,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                6,077,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -7,950,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                16,386,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                22,310,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                15,761,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,625,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                36,747,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                19,133,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | 
                                                461,034,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                328,947,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                426,967,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                316,335,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                313,376,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                406,588,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                395,396,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                303,267,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                329,583,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                247,398,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | — | 
                                                -211.23
                                                
                                             | — | 
                                                -290.48
                                                
                                             | — | — | — | — | 
                                                -275.91
                                                
                                             | 
                                                -325.35
                                                
                                             | — | 
                                                -223.39
                                                
                                             | 
                                                -201.02
                                                
                                             | — | — | — | 
                                                -218.11
                                                
                                             | 
                                                -288.70
                                                
                                             | 
                                                -143.94
                                                
                                             | — | — | 
                                                -210.61
                                                
                                             | 
| Basic earnings (loss) per share | — | — | 
                                                96.05
                                                
                                             | — | 
                                                49.35
                                                
                                             | — | 
                                                -111.40
                                                
                                             | 
                                                -69.22
                                                
                                             | — | — | 
                                                64.98
                                                
                                             | — | — | 
                                                50.54
                                                
                                             | 
                                                -84.19
                                                
                                             | 
                                                -56.88
                                                
                                             | — | — | — | 
                                                12.88
                                                
                                             | 
                                                22.76
                                                
                                             | — | 
| Diluted earnings per share | — | — | 
                                                26.39
                                                
                                             | — | 
                                                14.56
                                                
                                             | — |  |  | — | — | 
                                                19.31
                                                
                                             | — | — | 
                                                15.49
                                                
                                             |  |  | — | — | — | 
                                                5.58
                                                
                                             | 
                                                8.20
                                                
                                             | — | 
| Equity-to-asset ratio | — | 
                                                0.051
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.010
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                0.011
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                -0.025
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.052
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.055
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.040
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                -0.009
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.110
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.077
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | — | 
                                                1.8896
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                2.7511
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.8028
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.3323
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.2628
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | — | — | 
                                                3.51
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                6.83
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                6.02
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                7.74
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                37.10
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                21.01
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                51,175,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                62,747,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                44,157,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -25,591,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -20,806,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | — | 
                                                -4,181,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -1,567,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                7,889,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -3,787,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -2,250,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | — | 
                                                -298,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -5,851,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -17,057,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -4,197,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                9,478,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | 
                                                221,238,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                166,208,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                106,682,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                69,099,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                98,738,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Number of employees | 
                                                3,185
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,419
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1,648
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                234
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                3,496
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,721
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1,624
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,941
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                4,018
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,603
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                4,174
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                1,591
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                813
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                855
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                666
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                42
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                912
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                773
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                575
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                732
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                703
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                520
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                680
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                436
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |