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STOCK-BASED COMPENSATION (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award      
Stock-based compensation expense $ 26.6 $ 21.7 $ 21.8
Options exercised (in shares)   10,834 358,649
Payments for the purchase of shares to satisfy the employee income tax withholdings $ 6.2 $ 14.2 $ 11.0
Restricted Stock Units      
Share-based Compensation Arrangement by Share-based Payment Award      
Number of shares of common stock of which unit is convertible (in shares) 1    
Vesting period 3 years    
Qualified retirement eligibility age for grants awarded in and after 2017 55 years    
Qualified retirement eligibility number of years of service for grants awarded in and after 2017 10 years    
Stock options      
Share-based Compensation Arrangement by Share-based Payment Award      
Total intrinsic value of stock options exercised   $ 0.9 $ 26.0
RSAs and RSUs      
Share-based Compensation Arrangement by Share-based Payment Award      
Shares purchased to satisfy the employee income tax withholdings (in shares) 53,929    
Payments for the purchase of shares to satisfy the employee income tax withholdings $ 5.3    
Vested (in shares) 166,598 272,258 313,856
PSUs      
Share-based Compensation Arrangement by Share-based Payment Award      
Number of shares of common stock of which unit is convertible (in shares) 1    
Vesting period 3 years    
Shares purchased to satisfy the employee income tax withholdings (in shares) 9,982    
Payments for the purchase of shares to satisfy the employee income tax withholdings $ 0.9    
Vested (in shares) 29,468 48,053 69,372
Risk-free interest rate 0.15%    
Volatility time period 3 years    
Expected volatility 31.80%    
Correlation to S&P 500 Index time period 3 years    
Correlation with S&P index 0.51    
Unrecognized compensation expense $ 25.5    
Unrecognized compensation expense, period for recognition 1 year 8 months 12 days    
PSUs | Minimum      
Share-based Compensation Arrangement by Share-based Payment Award      
Units ultimately expected to be awarded 0.00%    
PSUs | Maximum      
Share-based Compensation Arrangement by Share-based Payment Award      
Units ultimately expected to be awarded 200.00%    
Restricted Stock      
Share-based Compensation Arrangement by Share-based Payment Award      
Vested (in shares) 149,071    
Restricted Stock | Director      
Share-based Compensation Arrangement by Share-based Payment Award      
Vesting period 1 year