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Share-Based Compensation Plans - Time-based Vesting Option Activity Additional Information (Details) - Time Based Vesting Option - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]      
Outstanding balance (in shares) 688,300    
Granted (shares) 0    
Forfeited or expired (shares) (31,100)    
Exercised (shares) (535,700)    
Outstanding balance (in shares) 121,500 688,300  
Exercisable (in shares) 121,500 700,000 700,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]      
Outstanding balance (in dollars per share) $ 26.01    
Granted (in dollars per share) 0.00    
Forfeited of expired (in dollars per share) 30.81    
Exercised (in dollars per share) 25.10    
Outstanding balance (in dollars per share) 28.80 $ 26.01  
Exercisable (in dollars per share) $ 28.80 $ 26.01 $ 26.44
Outstanding, Weighted- Average Remaining Contractual Term (in years) 10 months 24 days    
Exercisable, Weighted- Average Remaining Contractual Term (in years) 10 months 24 days    
Outstanding, Aggregate Intrinsic Value (in millions) $ 1.5    
Exercisable, Aggregate Intrinsic Value (in millions) $ 1.5    
Market price (in dollars per share) $ 41.25