Employees
| Concept | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | As at 2024-12-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Employees | ||||||||||||||||||
| Metrics related to human capital diversity | ||||||||||||||||||
| Metrics of consolidated subsidiaries | ||||||||||||||||||
| Consolidated subsidiaries | 
                                                いずみサポート㈱
                                                
                                             | 
                                                住友重機械モダン㈱
                                                
                                             | 
                                                住友重機械搬送システム㈱
                                                
                                             | 
                                                住友重機械プロセス機器㈱
                                                
                                             | 
                                                住友重機械イオンテクノロジー㈱
                                                
                                             | 
                                                住友重機械建機クレーン㈱
                                                
                                             | 
                                                住友重機械ギヤボックス㈱
                                                
                                             | 
                                                住友建機㈱
                                                
                                             | 
                                                住友重機械ハイマテックス㈱
                                                
                                             | 
                                                日本スピンドル製造㈱
                                                
                                             | 
                                                住友重機械マリンエンジニアリング㈱
                                                
                                             | 
                                                住重アテックス㈱
                                                
                                             | 
                                                住友重機械ファインテック㈱
                                                
                                             | 
                                                住友建機販売㈱
                                                
                                             | 
                                                ㈱イズミフードマシナリ
                                                
                                             | 
                                                新日本造機㈱
                                                
                                             | 
                                                住友重機械エンバイロメント㈱
                                                
                                             | 
                                                ㈱ライトウェル
                                                
                                             | 
| Ratio of female employees in managerial positions | 
                                                0.095
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.069
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.006
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.020
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.019
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.008
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.013
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.006
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.039
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.014
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.016
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.071
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Ratio of male employees taking childcare leave | ||||||||||||||||||
| All employees | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.857
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.742
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.733
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.840
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.778
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.800
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.667
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.667
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.000
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Differences in wages between male and female employees | ||||||||||||||||||
| All employees | 
                                                0.797
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.659
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.642
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.723
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.644
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.582
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.702
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.729
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.567
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.603
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.753
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Regular employees | 
                                                0.737
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.711
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.717
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.855
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.643
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.561
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.759
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.735
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.813
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.618
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.762
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
| Non-regular employees | 
                                                0.678
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.576
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.356
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.723
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.716
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.127
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.442
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.683
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.299
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                1.068
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                0.531
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             |