XML 84 R70.htm IDEA: XBRL DOCUMENT v3.20.4
Share-Based Compensation - Weighted Average Assumptions Used for Estimating Fair Values of Stock Options Granted (Detail) - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Payment Arrangement [Abstract]      
Expected volatility 22.20% 19.10% 17.30%
Expected term (years) 5 years 5 years 5 years
Risk-free interest rate 0.52% 2.25% 2.81%
Expected dividend yield 1.14% 0.66% 0.76%
Black-Scholes-Merton fair value per stock option granted (in USD per share) $ 11.01 $ 16.85 $ 14.12