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STOCK BASED COMPENSATION - Additional Information (Detail)
$ / shares in Units, $ in Millions
9 Months Ended
Sep. 30, 2017
USD ($)
$ / shares
shares
Stock Options  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Unrecognized compensation expenses related to stock options $ 32.9
Weighted average period of recognition for unrecognized compensation expenses 2 years 10 months 18 days
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]  
Weighted average period of recognition for unrecognized compensation expenses 3 years 9 months 19 days
Unrecognized compensation expenses related to RSUs $ 19.5
Share price grant date fair value | $ / shares $ 83.05
Restricted Stock Units (RSUs) | 2017 Plan  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Ratio of share reserve for RSUs granted 100.00%
Restricted Stock Units (RSUs) | 2008, 2011, and 2014 Plans  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Ratio of share reserve for RSUs granted 200.00%
Performance-Based Restricted Stock Units  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Share price grant date fair value | $ / shares $ 83.35
Total grant date fair value of shares $ 0.9
Maximum number of common shares issuable upon vesting | shares 10,348