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STOCK-BASED COMPENSATION (Details) - USD ($)
$ in Millions
 1 Months Ended 3 Months Ended 9 Months Ended
Feb. 28, 2023
Sep. 30, 2023
Sep. 30, 2022
Sep. 30, 2023
Sep. 30, 2022
Stock-based Compensation          
Stock-based compensation expense   $ 1.5 $ 7.0 $ 28.4 $ 23.1
Payments for the purchase of shares to satisfy the employee income tax withholdings       13.8 8.8
Director          
Stock-based Compensation          
Stock-based compensation expense   $ 0.5 $ 0.5 $ 1.4 $ 1.4
Restricted Stock Units          
Stock-based Compensation          
Number of shares of common stock of which unit is convertible (in shares)   1   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  
Restricted Stock Units | Non-employee Director          
Stock-based Compensation          
Vesting period       1 year  
PSUs          
Stock-based Compensation          
Number of shares of common stock of which unit is convertible (in shares)   1   1  
Vesting period       3 years  
Shares purchased to satisfy the employee income tax withholdings (in shares)       21,459  
Payments for the purchase of shares to satisfy the employee income tax withholdings       $ 2.7  
Vested (in shares)       55,399  
Risk-free interest rate 4.10%        
Volatility time period 3 years        
Expected volatility 33.50%        
Correlation to S&P 500 Index time period 3 years        
Correlation with S&P index 0.53        
Unrecognized compensation expense   $ 50.4   $ 50.4  
Unrecognized compensation expense, period for recognition       1 year 10 months 24 days  
PSUs | Minimum          
Stock-based Compensation          
Units ultimately expected to be awarded       0.00%  
PSUs | Maximum          
Stock-based Compensation          
Units ultimately expected to be awarded       200.00%  
Restricted Stock          
Stock-based Compensation          
Shares purchased to satisfy the employee income tax withholdings (in shares)       84,706  
Payments for the purchase of shares to satisfy the employee income tax withholdings       $ 11.1  
Shares vested, prompting share repurchases to cover employees' tax obligations       218,699