| Concept | As at 2025-03-31 | As at 2025-03-31 | As at 2025-03-31 | 
|---|---|---|---|
| Employees | |||
| Metrics related to human capital diversity | |||
| Metrics of consolidated subsidiaries | |||
| Consolidated subsidiaries | 
                                                株式会社
日本空調北陸
                                                
                                             | 
                                                日本空調システム
株式会社
                                                
                                             | 
                                                株式会社
日本空調東北
                                                
                                             | 
| Ratio of female employees in managerial positions | 
                                                0.061
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.150
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Ratio of male employees taking childcare leave | |||
| All employees | 
                                                0.500
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.250
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Differences in wages between male and female employees | |||
| All employees | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.718
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Regular employees | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.733
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Non-regular employees | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.630
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |