Key Financial Data Of Group
| Concept | 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 | 2019-04-01 to 2020-03-31 | As at 2020-03-31 | 2019-04-01 to 2020-03-31 | As at 2020-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Key financial data of group | ||||||||||||||||||||
| Business results of group | ||||||||||||||||||||
| Operating revenue | 
                                                36,269,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                31,709,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                32,071,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                41,185,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                28,703,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Ordinary income | — | 
                                                404,743,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                331,323,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                280,427,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                274,754,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                283,186,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | 
                                                21,103,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                56,937,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                19,883,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                50,050,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,444,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                76,086,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                24,993,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                60,427,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                13,385,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -5,250,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) attributable to owners of parent | — | 
                                                61,178,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                31,152,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                54,118,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                44,647,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                110,607,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Comprehensive income | — | 
                                                135,900,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -15,678,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                112,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                121,887,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                46,387,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | — | — | 
                                                1,021,746,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                567,644,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                567,713,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                901,750,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                941,066,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                589,965,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                958,833,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                585,010,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                853,062,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                575,199,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | — | 
                                                32,649,727,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                749,306,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                739,419,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                29,924,282,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                29,171,912,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                760,411,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                27,510,013,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                754,933,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                25,068,405,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                729,943,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | — | — | 
                                                5,397.27
                                                
                                             | 
                                                3,002.65
                                                
                                             | — | 
                                                3,024.51
                                                
                                             | 
                                                4,796.99
                                                
                                             | — | — | — | 
                                                4,949.87
                                                
                                             | 
                                                3,103.56
                                                
                                             | 
                                                5,043.70
                                                
                                             | — | — | 
                                                3,077.43
                                                
                                             | — | 
                                                4,487.30
                                                
                                             | — | 
                                                3,012.61
                                                
                                             | 
| Basic earnings (loss) per share | 
                                                85.00
                                                
                                             | 
                                                324.76
                                                
                                             | — | — | 
                                                11.96
                                                
                                             | — | — | 
                                                165.54
                                                
                                             | 
                                                116.10
                                                
                                             | 
                                                284.69
                                                
                                             | — | — | — | 
                                                139.70
                                                
                                             | 
                                                234.86
                                                
                                             | — | 
                                                66.10
                                                
                                             | — | 
                                                581.83
                                                
                                             | — | 
| Diluted earnings per share |  |  | — | — |  | — | — |  |  |  | — | — | — |  |  | — |  | — |  | — | 
| Equity-to-asset ratio | — | — | 
                                                0.0312
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.7575
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.7677
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0300
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0322
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.7758
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0348
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.7749
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.0340
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.7880
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | 
                                                0.0282
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0637
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0038
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0338
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0375
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0569
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.0458
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0492
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.0228
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.1356
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | 
                                                47.59
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                12.45
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                212.96
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                15.39
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                20.44
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8.33
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                15.02
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8.93
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                21.64
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                2.45
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                1,480,879,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -111,261,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,163,545,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                1,541,822,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                47,871,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -790,090,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                3,082,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -372,639,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                4,740,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -147,507,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -20,726,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -23,732,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -26,956,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -16,108,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -15,989,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | — | 
                                                8,445,177,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                7,708,412,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                7,840,263,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                6,076,226,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                4,545,697,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Number of employees | — | — | 
                                                7,995
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                304
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                273
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                7,546
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                7,830
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                299
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8,103
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                302
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                8,030
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                166
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | — | — | 
                                                2,763
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                47
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                42
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2,754
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                2,905
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                40
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,012
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                51
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                3,014
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                25
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |