Employees
| Concept | 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 | 
|---|---|---|---|---|---|
| Employees | |||||
| Metrics related to human capital diversity | |||||
| Metrics of consolidated subsidiaries | |||||
| Consolidated subsidiaries | 
                                                ワットラインサービス㈱
                                                
                                             | 
                                                タカオカ化成工業㈱
                                                
                                             | 
                                                東光器材㈱
                                                
                                             | 
                                                ㈱ミントウェーブ
                                                
                                             | 
                                                東光東芝メーターシステムズ㈱
                                                
                                             | 
| Ratio of female employees in managerial positions | 
                                                0.125
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.050
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.030
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Ratio of male employees taking childcare leave | |||||
| All employees | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.500
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Regular employees | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.500
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Non-regular employees | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Differences in wages between male and female employees | |||||
| All employees | 
                                                0.803
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.664
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.845
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.771
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.580
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Regular employees | 
                                                0.740
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.757
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.848
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.864
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.647
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Non-regular employees | 
                                                0.907
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.657
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.919
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.583
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.498
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |