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Common Stock - Assumption Used in Determination of Fair Value of Share Based Payment Awards (Detail)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]      
Expected volatility 35.90% 31.80% 36.10%
Risk-free interest rate 2.50% 2.70% 2.20%
Expected dividend yield 0.70% 0.60% 0.60%
Expected term (in years) 4 years 6 months 4 years 3 months 18 days 3 years