Key Financial Data Of Reporting Company
| 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 | As at 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 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 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Key financial data of reporting company | ||||||||||||||||||||||
| Business results of reporting company | ||||||||||||||||||||||
| Net sales | — | — | — | — | — | — | — | — | — | — | — | 
                                                786,509,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                709,641,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                682,912,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Operating revenue | — | — | — | — | — | — | — | — | — | 
                                                21,720,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                37,564,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                31,271,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,657,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Ordinary profit (loss) | — | — | — | — | — | — | — | — | — | 
                                                12,395,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                31,605,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                42,979,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                27,010,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                41,768,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -39,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                38,036,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Profit (loss) | — | — | — | — | — | — | — | — | — | 
                                                9,963,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                29,561,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                26,893,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -53,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Share capital | — | — | — | — | — | — | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total number of issued shares | — | — | — | — | — | — | 
                                                274,845,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                274,845,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | 
                                                274,845,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | — | — | — | 
                                                291,070,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
| Net assets | — | — | — | — | — | — | 
                                                366,902,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                398,521,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                275,155,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                275,226,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                362,315,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                355,865,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                270,476,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | — | — | — | — | — | 
                                                743,710,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                1,363,624,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                767,221,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                451,074,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                926,563,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                926,432,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                468,827,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | — | — | — | — | — | — | 
                                                1,053.64
                                                
                                             | — | — | — | — | — | 
                                                1,561.42
                                                
                                             | 
                                                1,087.42
                                                
                                             | — | 
                                                1,064.42
                                                
                                             | 
                                                1,396.72
                                                
                                             | — | — | — | 
                                                1,312.19
                                                
                                             | 
                                                1,002.30
                                                
                                             | 
| Dividend paid per share | — | — | — | — | — | — | — | — | — | 
                                                60.00
                                                
                                             | 
                                                60.00
                                                
                                             | — | — | — | 
                                                55.00
                                                
                                             | — | — | — | 
                                                40.00
                                                
                                             | — | — | — | 
| Interim dividend paid per share | — | — | — | — | — | — | — | — | — | 
                                                30.00
                                                
                                             | 
                                                25.00
                                                
                                             | — | — | — |  | — | — | — |  | — | — | — | 
| Basic earnings (loss) per share | — | — | — | — | — | — | — | — | — | 
                                                32.42
                                                
                                             | 
                                                115.44
                                                
                                             | 
                                                109.83
                                                
                                             | — | — | 
                                                101.64
                                                
                                             | — | — | 
                                                138.39
                                                
                                             | 
                                                -0.17
                                                
                                             | 
                                                94.73
                                                
                                             | — | — | 
| Diluted earnings per share | — | — | — | — | — | — | — | — | — |  |  |  | — | — |  | — | — |  |  |  | — | — | 
| Equity-to-asset ratio | — | — | — | — | — | — | 
                                                0.493
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                0.283
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.359
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.610
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.381
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.374
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.577
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | — | — | — | — | — | — | — | — | 
                                                0.031
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.107
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.074
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.099
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.103
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.087
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
| Price-earnings ratio | — | — | — | — | — | — | — | — | — | 
                                                37.2
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                12.5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                13.1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                10.1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                7.4
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                11.0
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
| Payout ratio | — | — | — | — | — | — | — | — | — | 
                                                1.851
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.520
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.541
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
| Net cash provided by (used in) operating activities | — | — | — | — | — | — | — | — | — | — | — | 
                                                11,372,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                70,954,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -16,333,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | — | — | — | — | — | — | — | — | — | — | — | 
                                                -260,898,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -5,293,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -22,547,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | — | — | — | — | — | — | — | — | — | — | — | 
                                                271,836,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -56,384,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                15,288,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                108,921,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                86,015,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                76,018,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Number of employees | 
                                                1,218
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,902
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                663
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2,763
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8,076
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                913
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                102
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                502
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                115
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                8,037
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                83
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                78
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                7,652
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                7,149
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                69
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                214
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                278
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                30
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                892
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                334
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                35
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                656
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                549
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                535
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Total shareholder return | — | — | — | — | — | — | 
                                                1.327
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                1.496
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1.034
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Total return on share price index | — | — | — | — | — | — | 
                                                1.895
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                1.739
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1.167
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |