v3.26.1
Share-Based Compensation - Narrative (Details)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
USD ($)
shares
Jun. 30, 2025
USD ($)
Jun. 30, 2026
USD ($)
shares
Jun. 30, 2025
USD ($)
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense     $ 9.3 $ 8.6
Share Units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Award vesting period     3 years  
Number of units granted (in shares) | shares     199,163 211,010
Value of units share units granted     $ 15.5 $ 13.8
Share-based compensation expense $ 2.0 $ 1.8 $ 7.7 $ 7.3
Performance Stock Units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Award vesting period     3 years  
Number of units granted (in shares) | shares     30,015 35,365
Value of units share units granted     $ 2.4 $ 2.3
Share-based compensation expense $ 0.7 $ 0.7 $ 1.6 $ 1.2
Performance Stock Units | Minimum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Potential payouts range 0   0  
Performance Stock Units | Maximum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Potential payouts range 1.50   1.50  
A.O. Smith Combined Compensation Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares available for granting of options or share units (in shares) | shares 1,890,715   1,890,715