Annual report pursuant to Section 13 and 15(d)

Benefit Plans - Fair Value of Options Granted (Details)

v3.20.4
Benefit Plans - Fair Value of Options Granted (Details)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Retirement Benefits [Abstract]      
Risk-free interest rate 1.00% 2.40% 2.70%
Expected life of options — years 3 years 10 months 28 days 3 years 4 months 28 days 4 years 4 months 17 days
Expected stock price volatility 28.00% 26.00% 23.00%
Expected dividend yield 0.80% 0.80% 0.70%