Key Financial Data Of Group
| Concept | As at 2025-03-31 | 2024-04-01 to 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 | 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 | ||||||||||||||||||||||
| Operating revenue | — | — | — | — | — | 
                                                34,071,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                35,040,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                18,040,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                29,340,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                15,030,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Ordinary income | — | 
                                                360,163,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                310,068,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                329,457,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                268,090,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                274,726,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | 
                                                82,801,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                31,837,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                32,839,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                63,042,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                15,770,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                46,631,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                27,016,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                64,992,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                12,266,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                54,108,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) attributable to owners of parent | — | 
                                                58,228,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                43,366,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                32,176,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                42,958,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                36,478,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Comprehensive income | — | 
                                                9,588,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                116,584,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -37,554,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -7,603,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                129,347,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | 
                                                966,012,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                641,587,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                989,399,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                642,533,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                641,476,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                904,779,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                959,063,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                642,261,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                998,906,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                646,900,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | 
                                                21,408,384,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                731,940,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                21,786,134,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                732,871,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                731,775,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,387,481,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                24,125,520,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                735,936,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                22,835,169,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                743,620,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | 
                                                981.17
                                                
                                             | — | — | — | 
                                                651.66
                                                
                                             | — | — | — | 
                                                973.55
                                                
                                             | 
                                                632.24
                                                
                                             | — | 
                                                602.58
                                                
                                             | 
                                                849.92
                                                
                                             | — | — | — | 
                                                888.10
                                                
                                             | 
                                                594.70
                                                
                                             | 
                                                861.05
                                                
                                             | — | — | 
                                                557.57
                                                
                                             | 
| Basic earnings (loss) per share | — | 
                                                58.38
                                                
                                             | — | — | — | 
                                                32.11
                                                
                                             | 
                                                31.72
                                                
                                             | 
                                                41.66
                                                
                                             | — | — | 
                                                14.84
                                                
                                             | — | — | 
                                                29.90
                                                
                                             | 
                                                24.70
                                                
                                             | 
                                                38.96
                                                
                                             | — | — | — | 
                                                10.91
                                                
                                             | 
                                                31.45
                                                
                                             | — | 
| Diluted earnings per share | — | 
                                                58.37
                                                
                                             | — | — | — | 
                                                32.10
                                                
                                             | 
                                                31.72
                                                
                                             | 
                                                41.66
                                                
                                             | — | — | 
                                                14.84
                                                
                                             | — | — | 
                                                29.89
                                                
                                             | 
                                                24.69
                                                
                                             | 
                                                38.95
                                                
                                             | — | — | — | 
                                                10.91
                                                
                                             | 
                                                31.43
                                                
                                             | — | 
| Equity-to-asset ratio | 
                                                0.0451
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.8765
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0454
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.8766
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.8765
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0422
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0397
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.8725
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0437
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.8697
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | 
                                                0.0595
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0498
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0514
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0457
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0248
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0345
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0422
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0438
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0195
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0387
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | — | 
                                                12.43
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                22.60
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                16.12
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                12.27
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                21.83
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                10.83
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                10.36
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                6.56
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                23.92
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8.29
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                -981,405,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -25,189,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -3,368,097,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,232,138,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                4,661,394,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -195,558,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -323,694,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                922,430,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -358,507,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -112,389,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -32,974,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -31,950,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -16,669,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -31,846,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -42,603,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | 
                                                3,211,554,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | 
                                                4,421,493,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                4,802,328,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                7,264,647,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                6,423,084,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Number of employees | 
                                                5,828
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                5,466
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                362
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                13
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                5,855
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                13
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                14
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                5,971
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                6,221
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                16
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                6,373
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                18
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                2,954
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                2,810
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                144
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                2,957
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,050
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                3,286
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,493
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |