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STOCK BASED COMPENSATION - Assumptions used in Black-Scholes Model (Detail) (USD $)
3 Months Ended 9 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Sep. 30, 2013
Sep. 30, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]        
Weighted average fair value at grant date $ 26.51 $ 20.68 $ 21.99 $ 20.09
Expected term (in years) 5 years 9 months 6 years 5 years 9 months 29 days 6 years
Expected volatility 26.20% 27.52% 27.05% 27.90%
Expected dividend yield 0.00% 0.00% 0.00% 0.00%
Risk free interest rate 1.67% 0.79% 1.00% 1.06%