v3.25.1
Stock Based Compensation - Narrative (Details)
$ in Millions
3 Months Ended
Mar. 31, 2025
USD ($)
shares
Mar. 31, 2024
USD ($)
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock based compensation expense $ 6.1 $ 8.3
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 209,366 189,792
Value of units share units granted $ 13.7 $ 15.6
Stock based compensation expense $ 5.5 $ 7.8
Performance Shares    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Award vesting period 3 years  
Number of units granted (in shares) | shares 35,365 28,390
Value of units share units granted $ 2.3 $ 2.3
Stock based compensation expense $ 0.5 $ 0.3
Performance Shares | Minimum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Potential payouts range 0  
Performance Shares | Maximum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Potential payouts range 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 2,079,233