Key Financial Data Of Group
| Concept | As at 2025-03-31 | 2024-04-01 to 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 | — | — | — | 
                                                114,917,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                29,550,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                22,931,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                20,802,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                24,815,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Ordinary income | — | 
                                                399,103,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                358,303,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                312,983,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                286,979,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                291,729,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | 
                                                122,764,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                113,600,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                28,329,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                77,004,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                21,700,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                79,870,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                19,406,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                82,257,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                23,441,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                41,405,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) attributable to owners of parent | — | 
                                                82,805,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                66,931,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                56,159,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                53,881,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                25,326,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Comprehensive income | — | 
                                                58,438,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                154,565,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                33,257,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                30,160,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                74,754,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | 
                                                1,292,594,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                958,884,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,284,767,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                894,555,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                897,300,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,161,255,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,164,626,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                912,180,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,159,099,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                916,305,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | 
                                                24,793,138,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                980,416,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                24,381,712,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                935,800,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                958,572,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                25,729,552,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                24,060,792,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,000,166,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,577,398,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,017,466,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | 
                                                1,128.09
                                                
                                             | — | 
                                                840.03
                                                
                                             | — | — | — | 
                                                1,098.40
                                                
                                             | 
                                                768.42
                                                
                                             | — | 
                                                764.22
                                                
                                             | 
                                                984.08
                                                
                                             | — | — | — | 
                                                965.47
                                                
                                             | 
                                                760.11
                                                
                                             | 
                                                955.81
                                                
                                             | — | — | 
                                                759.45
                                                
                                             | 
| Basic earnings (loss) per share | — | 
                                                71.63
                                                
                                             | — | 
                                                98.18
                                                
                                             | 
                                                24.18
                                                
                                             | 
                                                57.16
                                                
                                             | — | — | 
                                                18.16
                                                
                                             | — | — | 
                                                47.39
                                                
                                             | 
                                                16.08
                                                
                                             | 
                                                44.67
                                                
                                             | — | — | — | 
                                                19.40
                                                
                                             | 
                                                20.99
                                                
                                             | — | 
| Diluted earnings per share | — |  | — |  | 
                                                24.18
                                                
                                             | 
                                                57.16
                                                
                                             | — | — | 
                                                18.16
                                                
                                             | — | — | 
                                                47.39
                                                
                                             | 
                                                16.08
                                                
                                             | 
                                                44.67
                                                
                                             | — | — | — | 
                                                19.40
                                                
                                             | 
                                                20.99
                                                
                                             | — | 
| Equity-to-asset ratio | 
                                                0.0519
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.9780
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0524
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.9559
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.9360
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0449
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0481
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.9119
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0534
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.9005
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | 
                                                0.0645
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.1224
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0316
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0549
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0237
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0485
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0212
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0466
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0256
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0224
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | — | 
                                                13.69
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                9.99
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                31.83
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                13.46
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                26.87
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                10.29
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                28.47
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                10.25
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                23.13
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                21.38
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                376,257,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -2,217,487,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                965,540,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,247,289,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                2,039,109,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | 
                                                21,589,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                37,479,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -148,046,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                218,750,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -480,586,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -70,611,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -51,025,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -56,934,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -43,912,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                505,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | 
                                                4,353,143,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                4,025,908,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                6,256,941,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                5,496,374,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                4,074,238,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Number of employees | 
                                                5,941
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                5,815
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                5,604
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                5,825
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                9
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                5,995
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                8
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                3,272
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                3,282
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,325
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                3,708
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,885
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |