Key Financial Data Of Group
| Concept | As at 2024-09-30 | 2024-04-01 to 2024-09-30 | 2024-04-01 to 2024-09-30 | As at 2024-09-30 | 2023-04-01 to 2024-03-31 | 2023-04-01 to 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2023-09-30 | 2023-04-01 to 2023-09-30 | 2023-04-01 to 2023-09-30 | As at 2023-09-30 | 2022-04-01 to 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | As at 2022-09-30 | 2022-04-01 to 2022-09-30 | As at 2022-09-30 | 2022-04-01 to 2022-09-30 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Key financial data of group | ||||||||||||||||||||
| Business results of group | ||||||||||||||||||||
| Operating revenue | — | 
                                                20,651,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                35,040,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                16,620,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                18,040,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                8,020,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Ordinary income | — | — | 
                                                164,357,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                310,068,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                154,596,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                329,457,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                169,854,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | — | 
                                                19,506,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                46,059,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                32,839,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                63,042,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                33,534,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                15,326,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                15,770,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                46,631,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                6,801,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                38,670,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Profit (loss) attributable to owners of parent | — | — | 
                                                32,020,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                43,366,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                23,530,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                32,176,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                26,941,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Comprehensive income | — | — | 
                                                18,461,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                116,584,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                20,565,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -37,554,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -69,786,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                991,882,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                646,166,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                989,399,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                642,533,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                641,210,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                909,611,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                641,476,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                904,779,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                643,371,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                883,490,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Total assets | 
                                                21,282,779,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                736,458,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                21,786,134,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                732,871,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                734,985,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                21,124,604,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                731,775,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,387,481,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                733,658,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                21,320,055,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets per share | 
                                                992.21
                                                
                                             | — | — | — | — | — | 
                                                973.55
                                                
                                             | — | — | — | — | 
                                                875.80
                                                
                                             | — | — | 
                                                849.92
                                                
                                             | — | — | — | 
                                                817.61
                                                
                                             | — | 
| Basic earnings (loss) per share | — | — | 
                                                31.85
                                                
                                             | — | — | 
                                                41.66
                                                
                                             | — | — | — | 
                                                22.25
                                                
                                             | — | — | — | — | — | 
                                                29.90
                                                
                                             | — | — | — | 
                                                24.94
                                                
                                             | 
| Diluted earnings per share | — | — | 
                                                31.84
                                                
                                             | — | — | 
                                                41.66
                                                
                                             | — | — | — | 
                                                22.25
                                                
                                             | — | — | — | — | — | 
                                                29.89
                                                
                                             | — | — | — | 
                                                24.93
                                                
                                             | 
| Equity-to-asset ratio | 
                                                0.0466
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.8773
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0454
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.8766
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.8723
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.0430
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.8765
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.0422
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.8768
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.0414
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                -547,789,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -23,541,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -566,820,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -3,368,097,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -3,107,725,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) investing activities | — | — | 
                                                -398,410,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -325,343,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                99,279,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                922,430,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                376,381,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net cash provided by (used in) financing activities | — | — | 
                                                -15,977,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -31,950,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -15,719,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -16,669,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -5,726,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and cash equivalents | 
                                                3,459,315,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                4,421,493,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                4,319,068,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                4,802,328,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                4,527,609,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Number of employees | 
                                                5,940
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                13
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                5,855
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                13
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                13
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                6,013
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                14
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                5,971
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                14
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                6,174
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Average number of temporary employees | 
                                                2,969
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                2,957
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                2,959
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,050
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                3,109
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — |