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Share-based Compensation - Schedule of Assumptions Used in Determining Fair Value of Stock Options Granted (Detail) - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions And Methodology [Abstract]      
Expected term (in years) 5 years 4 years 6 months 4 years 6 months
Expected volatility     31.20%
Expected volatility, minimum 29.70% 28.70%  
Expected volatility, maximum 31.00% 30.10%  
Risk free interest rate     1.93%
Risk free interest rate, minimum 1.38% 2.55%  
Risk free interest rate, maximum 2.31% 2.79%  
Weighted average grant date fair value $ 14.64 $ 16.28 $ 13.32