Directors (And Other Officers)
| Concept | 
                                    
                                        As at 2025-06-26  | 
                            
                                
                                    
                                        As at 2025-06-26  | 
                            
                                
                                    
                                        As at 2025-06-26  | 
                            
                                
                                    
                                        As at 2025-06-26  | 
                            
                                
                                    
                                        As at 2025-06-26  | 
                            
                                
                                    
                                        As at 2025-06-26  | 
                            
                                
                                    
                                        As at 2025-06-26  | 
                            
                                
                                    
                                        As at 2025-06-26  | 
                            
                                
                                    
                                        As at 2025-06-26  | 
                            
                                
                                    
                                        As at 2025-06-26  | 
                            
                        
|---|---|---|---|---|---|---|---|---|---|---|
| Directors (and other officers) | ||||||||||
| Information about directors (and corporate auditors) (Proposal) | ||||||||||
| Official title or position | — | 
                                        
                                             
                                                取締役
執行役員 企画部長
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                取締役
執行役員 パイル事業本部長兼土木営業部長
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                取締役
執行役員 海外部長
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                代表取締役社長
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                取締役
執行役員 管理本部長
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                取締役
(監査等委員)
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                取締役
(監査等委員)
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                取締役
執行役員 開発担当
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                取締役
(監査等委員)
                                                
                                             
                                        
                                     | 
                                
                            
| Name | — | 
                                        
                                             
                                                佐野 雅哉
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                黒河  徹
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                高橋 勝規
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                若尾  直
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                谷山 敦之
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                水井 利行
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                久保 知一
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                又吉 直哉
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                鈴木 みき
                                                
                                             
                                        
                                     | 
                                
                            
| Date of birth | — | 
                                        
                                             
                                                1964-08-10
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1973-09-28
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1959-09-22
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1959-04-11
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1969-07-31
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1961-02-25
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1972-12-03
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1967-01-15
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1972-05-31
                                                
                                             
                                        
                                     | 
                                
                            
| Career summary | — | |||||||||
| Term of office | — | 
                                        
                                             
                                                (注)4
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                (注)4
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                (注)4
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                (注)4
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                (注)4
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                (注)5
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                (注)5
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                (注)4
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                (注)5
                                                
                                             
                                        
                                     | 
                                
                            
| Number of shares held (Ordinary shares) | 
                                        
                                             
                                                54,684
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                956
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                5,395
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                23,276
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                11,761
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                3,193
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                100
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                300
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                9,503
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                200
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     |