Key Financial Data Of Reporting Company
| Concept | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | 2023-04-01 to 2024-03-31 | 2023-04-01 to 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | 2022-04-01 to 2023-03-31 | 2022-04-01 to 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | 2021-04-01 to 2022-03-31 | 2021-04-01 to 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2021-03-31 | 2020-04-01 to 2021-03-31 | 2020-04-01 to 2021-03-31 | As at 2021-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Key financial data of reporting company | ||||||||||||||||||||||||||||||||||||
| Business results of reporting company | ||||||||||||||||||||||||||||||||||||
| Net sales | — | — | — | — | — | — | 
                                                2,588,700,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                1,097,714,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,024,291,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,387,240,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                983,554,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,616,066,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                777,239,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,280,775,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                561,745,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,608,414,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | — | — | — | — | — | 
                                                490,866,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                282,004,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                272,871,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                261,341,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                628,651,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,109,790,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                434,140,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,003,154,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                90,960,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                215,336,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                285,359,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                259,059,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                600,344,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                488,220,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                38,252,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Share capital | — | — | — | — | — | — | — | — | — | — | — | 
                                                144,319,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | 
                                                144,319,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                144,319,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                144,319,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                144,319,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total number of issued shares | — | — | — | — | — | — | — | — | — | — | — | 
                                                461,000,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | 
                                                510,165,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | 
                                                510,165,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | — | — | 
                                                170,055,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | — | — | — | 
                                                170,055,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             | 
| Net assets | — | — | — | — | — | 
                                                2,969,973,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                929,201,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | 
                                                2,693,365,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                835,968,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                884,221,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,524,993,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,759,073,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                678,184,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                667,411,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                249,490,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | — | — | — | — | 
                                                4,320,269,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                1,833,939,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | 
                                                4,254,770,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,938,047,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,726,420,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,776,797,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,080,023,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,592,888,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,125,480,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,333,529,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | — | — | — | — | — | 
                                                6,735.03
                                                
                                             | — | — | — | — | — | 
                                                2,144.01
                                                
                                             | — | — | — | — | — | — | — | — | — | — | 
                                                5,772.50
                                                
                                             | 
                                                1,820.71
                                                
                                             | — | — | 
                                                1,739.97
                                                
                                             | 
                                                4,877.55
                                                
                                             | — | — | 
                                                3,381.43
                                                
                                             | 
                                                1,338.15
                                                
                                             | 
                                                3,703.27
                                                
                                             | — | — | 
                                                1,477.48
                                                
                                             | 
| Dividend paid per share | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                325.00
                                                
                                             | — | — | — | 
                                                140.00
                                                
                                             | — | — | — | 
                                                520.00
                                                
                                             | — | — | — | 
                                                1,450.00
                                                
                                             | — | — | — | — | 
                                                200.00
                                                
                                             | — | — | 
| Interim dividend paid per share | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                130.00
                                                
                                             | — | — | — | 
                                                60.00
                                                
                                             | — | — | — | 
                                                350.00
                                                
                                             | — | — | — | 
                                                200.00
                                                
                                             | — | — | — | — | 
                                                20.00
                                                
                                             | — | — | 
| Basic earnings (loss) per share | — | — | — | — | — | — | 
                                                1,070.32
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                639.35
                                                
                                             | — | — | — | 
                                                530.49
                                                
                                             | 
                                                468.13
                                                
                                             | — | — | 
                                                1,182.09
                                                
                                             | 
                                                1,993.71
                                                
                                             | — | — | 
                                                963.39
                                                
                                             | 
                                                1,991.25
                                                
                                             | — | — | — | 
                                                226.54
                                                
                                             | 
                                                824.55
                                                
                                             | — | 
| Diluted earnings per share | — | — | — | — | — | — |  | — | — | — | — | — | — | — | — | — |  | — | — | — |  |  | — | — |  |  | — | — |  |  | — | — | — |  |  | — | 
| Equity-to-asset ratio | — | — | — | — | — | 
                                                0.676
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                0.507
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | 
                                                0.623
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.431
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.512
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.656
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.556
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.426
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.294
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.187
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | — | — | — | — | — | 
                                                0.172
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                0.323
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.301
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.089
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.768
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.483
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                1.053
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.860
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.165
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.256
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | — | — | — | — | — | — | 
                                                4.6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | 
                                                7.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                7.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                2.6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                3.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.8
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                16.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                4.6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Payout ratio | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                0.508
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.264
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.440
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.502
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                0.883
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | — | — | — | — | — | 
                                                510,755,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                401,414,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                824,853,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                507,762,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                159,336,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | — | — | — | — | — | 
                                                -59,783,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                -285,631,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -252,964,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -148,571,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -16,871,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | — | — | — | — | — | 
                                                -427,747,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                -163,420,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -581,203,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -237,535,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -125,483,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | — | — | — | — | 
                                                149,859,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                144,858,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                196,231,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                226,694,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                103,593,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Number of employees | 
                                                24
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,039
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,455
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                472
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                343
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                35,230
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                56
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,605
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                2
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                195
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,336
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,872
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                472
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                243
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                626
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                25,202
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                959
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                35,243
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,312
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                1,299
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                35,502
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                35,165
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,249
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                35,057
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                1,217
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                161
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                164
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                81
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                31
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                14,949
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                3,109
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                34
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                191
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                280
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                81
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                34
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                75
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                11,018
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                61
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                11,738
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                190
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                184
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                11,043
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                11,200
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                158
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                10,987
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                144
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Total shareholder return | — | — | — | — | — | — | — | — | — | — | — | 
                                                15.061
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | 
                                                12.324
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                9.702
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                9.650
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                3.091
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Total return on share price index | — | — | — | — | — | — | — | — | — | — | — | 
                                                2.134
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | 
                                                2.168
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                1.534
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                1.450
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                1.421
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |