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Stock-Based Compensation Plans (Details 5) - Performance awards - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]      
Dividend yield (as a percent) 3.10% 3.70% 3.20%
Estimated volatility, minimum (as a percent) 13.90% 15.30% 15.20%
Estimated volatility, maximum (as a percent) 18.80% 19.70% 22.80%
Risk-free interest rate, minimum (as a percent) 2.46% 0.69% 0.44%
Risk-free interest rate, maximum (as a percent) 2.57% 1.61% 0.88%
Estimated performance award value based on total shareholder return measure (in dollars per share) $ 204.15 $ 151.67 $ 175.86
Historical volatility (as a percent) 50.00% 50.00% 50.00%
Implied volatility (as a percent) 50.00% 50.00% 50.00%
Market closing price (in dollars per share) $ 195.86 $ 161.10 $ 179.07