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EMPLOYEE BENEFIT PLANS - Weighted-Average Fair Value of Stock Options (Detail) - Employee Stock Options - $ / shares
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted-average fair value at grant date (in dollars per share) $ 49.81 $ 37.12 $ 36.91
Expected option life (years) 4 years 1 month 4 years 2 months 1 day 4 years 2 months 1 day
Expected volatility 27.10% 27.60% 27.40%
Risk-free interest rate at grant date 2.00% 1.10% 1.40%
Dividend yield 0.70% 0.70% 0.70%