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Stock-Based Compensation Plans (Details 5) - Performance awards - $ / shares
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]      
Dividend yield (as a percent) 3.30% 3.00% 3.60%
Estimated volatility, minimum (as a percent) 15.20% 12.00% 17.60%
Estimated volatility, maximum (as a percent) 22.80% 17.30% 18.60%
Risk-free interest rate, minimum (as a percent) 0.44% 0.07% 0.04%
Risk-free interest rate, maximum (as a percent) 0.88% 1.09% 0.72%
Estimated performance award value based on total shareholder return measure (in dollars per share) $ 131.24 $ 139.18 $ 103.20
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) $ 161.66 $ 166.23 $ 128.97