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STOCK BASED COMPENSATION - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Intrinsic value of options exercised   $ 0.6
Stock Options    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Unrecognized compensation expenses related to stock options $ 18.1  
Weighted average period of recognition for unrecognized compensation expenses 2 years 9 months 18 days  
Award vesting period 3 years  
Restricted Stock Units (RSUs)    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Weighted average period of recognition for unrecognized compensation expenses 3 years 2 months 12 days  
Award vesting period 3 years  
Unrecognized compensation expenses related to RSUs $ 29.0  
Fair value of units vested (in shares) 3.9  
Performance-Based Restricted Stock Units    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Unrecognized compensation expenses related to RSUs $ 5.0  
Additional shares expected to vest 249,000