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STOCK BASED COMPENSATION - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Intrinsic value of options exercised $ 3.3 $ 0.3 $ 4.8 $ 3.5
Stock Options        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Unrecognized compensation expenses related to stock options 21.9   $ 21.9  
Weighted average period of recognition for unrecognized compensation expenses     2 years 9 months  
Stock Options | Director        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Award vesting period     1 year  
Stock Options | Officers And Employees        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Award vesting period     5 years  
Restricted Stock Units (RSUs)        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Award vesting period     5 years  
Weighted average period of recognition for unrecognized compensation expenses     3 years 8 months 12 days  
Unrecognized compensation expenses related to RSUs 25.7   $ 25.7  
Fair value of units vested (in shares)     4.2  
Performance-Based Restricted Stock Units        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Unrecognized compensation expenses related to RSUs $ 1.7   $ 1.7  
Additional shares expected to vest     315,000