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Share-Based Compensation Plans - Schedule of Valuation Assumptions for Non-Qualified Stock Options (Details) - Non-qualified Stock Options
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2016
USD ($)
grant_date
$ / shares
shares
Dec. 31, 2015
USD ($)
$ / shares
shares
Dec. 31, 2014
USD ($)
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest rate 1.67% 1.61% 1.72%
Dividend yield 0.16% 0.12% 0.15%
Volatility factor 28.59% 26.80% 24.80%
Expected term (in years) 5 years 5 years 5 years
Number of Options Granted (in shares) | shares 228,500 158,200 133,500
Weighted average grant date fair value (in dollars per share) | $ / shares $ 15.10 $ 19.90 $ 22.25
Total intrinsic value of options exercised | $ $ 3.5 $ 15.1 $ 14.4
Number of grant dates | grant_date 2