Major Shareholders
| Concept | 
                                    
                                        As at 2024-09-30  | 
                            
                                
                                    
                                        As at 2024-09-30  | 
                            
                                
                                    
                                        As at 2024-09-30  | 
                            
                                
                                    
                                        As at 2024-09-30  | 
                            
                                
                                    
                                        As at 2024-09-30  | 
                            
                                
                                    
                                        As at 2024-09-30  | 
                            
                                
                                    
                                        As at 2024-09-30  | 
                            
                                
                                    
                                        As at 2024-09-30  | 
                            
                                
                                    
                                        As at 2024-09-30  | 
                            
                                
                                    
                                        As at 2024-09-30  | 
                            
                                
                                    
                                        As at 2024-09-30  | 
                            
                        
|---|---|---|---|---|---|---|---|---|---|---|---|
| Major shareholders | |||||||||||
| Major shareholders | |||||||||||
| Name | 
                                        
                                             
                                                吉田 均
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                ヨシタケ社員持株会
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                松栄金属(株)
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                槇田 重夫
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                東芳工業(株)
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                光通信(株)
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                (有)プラスファイブ
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                DAIWA CM SINGAPORE LTD-NOMINEE PLUS SEVEN PTE. LTD.
(常任代理人 大和証券(株))
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                島 亜紀
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                (株)昭和螺旋管製作所
                                                
                                             
                                        
                                     | 
                                
                            
| Address | 
                                        
                                             
                                                愛知県一宮市
                                                
                                             
                                        
                                     | 
                                
                                    — | 
                                        
                                             
                                                愛知県名古屋市昭和区御器所通2丁目27-1
㈱ヨシタケ内
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                京都府宇治市宇治妙楽198
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                愛知県豊橋市
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                東京都目黒区中央町1丁目2-4
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                東京都豊島区西池袋1丁目4-10
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                名古屋市昭和区田面町2丁目45-3
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                7 STRAITS VIEW MARINA ONE EAST
TOWER, #16-05 AND #16-06 SINGAPORE
(東京都千代田区丸の内1丁目9-1)
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                名古屋市中区
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                東京都板橋区小豆沢2丁目26-10
                                                
                                             
                                        
                                     | 
                                
                            
| Number of shares held | 
                                        
                                             
                                                175,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                7,556,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                149,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                166,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                189,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                206,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                191,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                4,659,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                1,395,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                175,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                247,000
                                                
                                                    
                                                        xbrli:shares
                                                    
                                                
                                             
                                        
                                     | 
                                
                            
| Shareholding ratio (excluding treasury shares) | 
                                        
                                             
                                                0.0138
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                0.5941
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                0.0117
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                0.0130
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                0.0149
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                0.0162
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                0.0150
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                0.3663
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                0.1097
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                0.0137
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     | 
                                
                                    
                                        
                                             
                                                0.0194
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             
                                        
                                     |