Key Financial Data Of Group
| Concept | As at 2024-03-31 | 2023-04-01 to 2024-03-31 | 2023-04-01 to 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | 2022-04-01 to 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | 2021-04-01 to 2022-03-31 | 2021-04-01 to 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2021-03-31 | 2020-04-01 to 2021-03-31 | 2020-04-01 to 2021-03-31 | As at 2021-03-31 | 2019-04-01 to 2020-03-31 | As at 2020-03-31 | 2019-04-01 to 2020-03-31 | As at 2020-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Key financial data of group | ||||||||||||||||||||||||
| Business results of group | ||||||||||||||||||||||||
| Net sales | — | — | 
                                                1,022,531,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                951,247,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                729,969,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                544,737,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                590,593,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Operating revenue | — | 
                                                31,122,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                6,337,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                189,296,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                371,991,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                399,109,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Ordinary profit (loss) | — | 
                                                28,504,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                80,499,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                4,064,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                66,721,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,609,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                44,565,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                12,019,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                34,140,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                18,472,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                39,985,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) attributable to owners of parent | — | — | 
                                                52,347,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                40,545,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                34,377,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                21,602,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                26,176,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Comprehensive income | — | — | 
                                                48,907,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                44,798,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                29,583,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                24,350,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                27,169,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | — | — | — | 
                                                515,176,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                360,726,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                350,295,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                482,718,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                460,130,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                364,601,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                246,220,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                178,068,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                229,304,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                170,931,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | — | — | 
                                                724,747,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                497,305,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                488,354,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                688,132,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                652,524,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                417,609,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                368,936,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                317,203,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                351,809,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                306,487,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | — | — | — | 
                                                1,233.84
                                                
                                             | — | 
                                                864.66
                                                
                                             | — | — | — | 
                                                837.52
                                                
                                             | 
                                                1,153.58
                                                
                                             | — | — | — | 
                                                1,085.07
                                                
                                             | 
                                                859.82
                                                
                                             | 
                                                799.37
                                                
                                             | — | — | 
                                                578.07
                                                
                                             | — | 
                                                744.51
                                                
                                             | — | 
                                                554.95
                                                
                                             | 
| Basic earnings (loss) per share | — | 
                                                73.00
                                                
                                             | 
                                                125.31
                                                
                                             | — | — | — | — | — | 
                                                9.26
                                                
                                             | — | — | 
                                                96.02
                                                
                                             | 
                                                43.28
                                                
                                             | 
                                                93.81
                                                
                                             | — | — | — | 
                                                37.61
                                                
                                             | 
                                                70.15
                                                
                                             | — | 
                                                58.10
                                                
                                             | — | 
                                                85.01
                                                
                                             | — | 
| Diluted earnings per share | — | 
                                                72.98
                                                
                                             | 
                                                125.28
                                                
                                             | — | — | — | — | — | 
                                                9.25
                                                
                                             | — | — | 
                                                95.99
                                                
                                             | 
                                                43.27
                                                
                                             | 
                                                93.78
                                                
                                             | — | — | — | 
                                                37.59
                                                
                                             | 
                                                70.12
                                                
                                             | — | 
                                                58.08
                                                
                                             | — | 
                                                84.98
                                                
                                             | — | 
| Equity-to-asset ratio | — | — | — | 
                                                0.710
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.725
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.717
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.701
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.705
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.873
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.667
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.561
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.652
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.558
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | 
                                                0.086
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.105
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                0.011
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.086
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.058
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.097
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.066
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.091
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.108
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.119
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | — | 
                                                33.4
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                19.5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | — | 
                                                252.5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                24.3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                33.4
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                15.4
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                43.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                23.5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                22.5
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                15.4
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                63,506,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                64,061,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                39,812,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                25,875,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                24,764,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | — | 
                                                -22,760,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                -19,669,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -15,485,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -6,311,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -48,840,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | — | 
                                                -18,273,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | 
                                                -23,734,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -20,337,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -9,409,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                9,089,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | — | — | 
                                                117,720,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                95,224,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                74,519,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                38,517,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                28,363,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Number of employees | 
                                                68
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                13,371
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                630
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                68
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                6,534
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                6,207
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                68
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                13,657
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                13,321
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                72
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                6,692
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                526
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                6,569
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                498
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Average number of temporary employees | 
                                                6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                15,267
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1,857
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8,627
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                4,783
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                14,807
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                14,575
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                7,974
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                61
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                8,097
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                62
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |