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STOCK BASED COMPENSATION - Assumptions used in Black-Scholes Model (Detail) - $ / shares
3 Months Ended 6 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]        
Stock options granted (shares) 31,538 74,742 1,040,107 935,276
Weighted average fair value at grant date $ 19.69 $ 22.18 $ 20.17 $ 22.80
Expected term (in years) 4 years 9 months 18 days 4 years 9 months 15 days 4 years 9 months 7 days 4 years 9 months 15 days
Expected volatility 20.96% 15.98% 18.11% 16.58%
Expected dividend yield 0.00% 0.00% 0.00% 0.00%
Risk free interest rate 1.26% 1.43% 1.22% 1.44%