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Share-Based Compensation - Stock Options, Schedule of Assumptions for Fair Value of Options Granted (Details) - Stock Options
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest rate 2.50% 2.10% 2.00%
Weighted average expected life 5 years 8 months 12 days 5 years 9 months 18 days 5 years 9 months 18 days
Expected volatility 22.60% 21.50% 25.10%
Dividend yield 1.90% 1.50% 1.90%