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Share-Based Payments - Method and Assumptions on Valuation of Stock Options and Awards (Details) - Stock Option Plan - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Schedule of Share-based Compensation Assumptions [Line Items]      
Expected life (in years) 7 years 10 months 6 days 7 years 7 months 20 days 7 years 3 days
Volatility 30.00% 32.37% 35.00%
Risk free interest rate 1.90% 3.10% 2.14%
Dividend yield 0.76% 0.61% 0.50%
Weighted-average fair value at the grant date (in dollars per share) $ 17.12 $ 21.03 $ 21.11
Expected stock volatility rate, low end of range 30.00% 31.72% 28.19%
Expected stock volatility rate, high end of range 38.17% 36.73% 35.00%