XML 22 R82.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Share-Based Compensation Plans - Assumptions Used to Determine Weighted-Average Fair Value of Options Granted (Details)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Payment Arrangement [Abstract]      
Expected dividend yield 3.20% 3.40% 3.60%
Risk-free interest rate 2.40% 2.90% 2.00%
Expected volatility 18.70% 19.10% 17.80%
Expected life (years) 5 years 10 months 24 days 6 years 1 month 6 days 6 years 1 month 6 days