Key Financial Data Of Group
| Concept | As at 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | 2023-04-01 to 2024-03-31 | 2023-04-01 to 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | 2022-04-01 to 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | 2021-04-01 to 2022-03-31 | 2021-04-01 to 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2021-03-31 | 2020-04-01 to 2021-03-31 | 2020-04-01 to 2021-03-31 | As at 2021-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Key financial data of group | ||||||||||||||||||||||
| Business results of group | ||||||||||||||||||||||
| Net sales | — | — | 
                                                84,190,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                78,157,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                68,443,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                73,688,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                56,548,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                61,030,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                51,764,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                56,905,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                50,584,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                54,871,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Ordinary profit (loss) | — | — | 
                                                9,935,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                9,539,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,146,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,374,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,403,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,557,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,200,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,385,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,935,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,128,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Profit (loss) attributable to owners of parent | — | — | 
                                                7,256,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                4,506,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                2,339,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,237,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                1,234,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Comprehensive income | — | — | 
                                                5,496,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                7,594,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                1,696,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,719,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                3,899,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net assets | — | 
                                                52,948,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                47,564,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                49,186,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                42,974,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                38,967,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                43,375,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                42,462,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                37,940,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                41,282,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                36,746,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Total assets | — | 
                                                80,163,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                72,555,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                76,228,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                67,111,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                57,113,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                63,457,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                63,698,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                57,176,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                62,443,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                55,638,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets per share | — | 
                                                2,516.40
                                                
                                             | — | 
                                                2,260.66
                                                
                                             | — | — | — | — | 
                                                2,337.72
                                                
                                             | 
                                                2,042.56
                                                
                                             | — | 
                                                1,789.85
                                                
                                             | 
                                                1,992.31
                                                
                                             | — | — | — | 
                                                1,950.36
                                                
                                             | 
                                                1,742.66
                                                
                                             | 
                                                1,896.12
                                                
                                             | — | — | 
                                                1,687.81
                                                
                                             | 
| Basic earnings (loss) per share | — | — | 
                                                344.90
                                                
                                             | — | — | 
                                                334.28
                                                
                                             | 
                                                204.01
                                                
                                             | 
                                                209.44
                                                
                                             | — | — | 
                                                104.51
                                                
                                             | — | — | 
                                                107.43
                                                
                                             | 
                                                98.24
                                                
                                             | 
                                                102.76
                                                
                                             | — | — | — | 
                                                52.37
                                                
                                             | 
                                                56.11
                                                
                                             | — | 
| Diluted earnings per share | — | — |  | — | — |  |  |  | — | — |  | — | — |  |  |  | — | — | — |  |  | — | 
| Equity-to-asset ratio | — | 
                                                0.660
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.656
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | — | 
                                                0.645
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.640
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.682
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.684
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.667
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.664
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.661
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.660
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Rate of return on equity | — | — | 
                                                0.142
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.155
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.107
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.097
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.059
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                0.054
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.057
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.053
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                0.032
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.031
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Price-earnings ratio | — | — | 
                                                7.6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                7.8
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                9.9
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                9.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                8.3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                8.1
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                8.3
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                16.7
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                15.6
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                4,651,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -1,453,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -157,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                904,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                1,136,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | — | 
                                                -159,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -340,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -625,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -130,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -1,295,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | — | 
                                                -1,790,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -1,723,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | 
                                                -883,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -565,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                -1,113,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | 
                                                11,533,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                8,847,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                12,340,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                13,968,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                13,686,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Number of employees | 
                                                114
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                940
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                810
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                141
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                899
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                776
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                775
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                901
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | — | 
                                                870
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                744
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                848
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — | 
                                                725
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |