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Equity-Based Compensation Plans (Fair Value of Performance Share Awards) (Details) - Performance stock awards [Member] - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock price as of valuation date (in dollars per share) $ 35.01 $ 54.00 $ 43.60
Risk-free rate 2.47% 2.46% 1.61%
Expected volatility 25.15% 23.74% 24.22%
Expected dividend yield [1]   2.96% 3.44%
Expected term (years) 3 years 3 years 3 years
Fair value of a performance share $ 37.87 $ 75.37 $ 53.85
[1] For 2019 assumes full dividend reinvestment