Key Financial Data Of Group
| Concept | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | 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 | — | — | — | — | — | — | 
                                                24,591,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,702,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                17,837,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                9,903,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                10,397,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Ordinary income | — | — | — | 
                                                201,368,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                186,071,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                160,234,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                146,085,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                115,478,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | — | — | 
                                                52,176,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                21,886,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                19,339,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                34,151,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                15,902,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                18,780,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,287,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                27,070,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                9,453,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                31,042,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) attributable to owners of parent | — | — | — | 
                                                35,835,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                27,691,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                12,508,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                22,906,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                21,574,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Comprehensive income | — | — | — | 
                                                -13,311,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                52,066,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                10,235,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -12,817,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                43,243,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | — | — | 
                                                504,636,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                464,458,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                535,249,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                459,897,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                456,298,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                498,604,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                496,200,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                448,270,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                516,880,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                447,487,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | — | 
                                                12,131,905,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                467,660,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                12,790,381,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                463,379,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                457,008,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                11,496,027,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                11,603,909,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                448,976,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                11,009,572,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                448,191,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | — | — | 
                                                1,679.10
                                                
                                             | — | — | 
                                                1,544.67
                                                
                                             | — | — | — | 
                                                1,760.62
                                                
                                             | 
                                                1,512.13
                                                
                                             | — | 
                                                1,467.63
                                                
                                             | 
                                                1,603.30
                                                
                                             | — | — | — | 
                                                1,596.79
                                                
                                             | 
                                                1,442.91
                                                
                                             | 
                                                1,664.01
                                                
                                             | — | — | 
                                                1,440.89
                                                
                                             | 
| Basic earnings (loss) per share | — | — | — | 
                                                118.55
                                                
                                             | — | — | 
                                                72.10
                                                
                                             | 
                                                62.79
                                                
                                             | 
                                                90.35
                                                
                                             | — | — | 
                                                50.92
                                                
                                             | — | — | 
                                                40.25
                                                
                                             | 
                                                26.42
                                                
                                             | 
                                                73.75
                                                
                                             | — | — | — | 
                                                30.30
                                                
                                             | 
                                                69.26
                                                
                                             | — | 
| Diluted earnings per share | — | — | — | 
                                                118.49
                                                
                                             | — | — | 
                                                72.06
                                                
                                             | 
                                                62.75
                                                
                                             | 
                                                90.30
                                                
                                             | — | — | 
                                                50.90
                                                
                                             | — | — | 
                                                40.22
                                                
                                             | 
                                                26.40
                                                
                                             | 
                                                73.71
                                                
                                             | — | — | — | 
                                                30.28
                                                
                                             | 
                                                69.22
                                                
                                             | — | 
| Equity-to-asset ratio | — | — | 
                                                0.0415
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.9928
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0418
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.9922
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.9981
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0433
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0427
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.9981
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0469
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.9981
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | — | — | 
                                                0.0689
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0472
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0420
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0535
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0350
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0251
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0183
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0452
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0212
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0432
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | — | — | — | 
                                                10.21
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                16.80
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                17.37
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                12.07
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                12.29
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                15.55
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                24.52
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8.78
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                22.34
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                9.77
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | — | — | 
                                                -897,433,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                783,335,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -468,742,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                216,889,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                1,486,338,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | — | — | 
                                                -202,518,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -119,386,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                65,827,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -198,327,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -370,404,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | — | — | 
                                                -17,718,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -15,919,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -8,100,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -22,637,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -9,312,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | — | 
                                                1,685,379,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                2,803,038,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                2,154,953,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                2,565,955,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,570,007,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Number of employees | 
                                                2,846
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                103
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,689
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                740
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                17
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                3,682
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                15
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                17
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,739
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                3,798
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                10
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,813
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                11
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                1,059
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                22
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,365
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                284
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                1,320
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                2
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,357
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                1,456
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,376
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |