Employee Benefits (Other Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax	$ 55.8	$ (96.7)	$ 113.5
Settlement loss	$ 0.0	$ (28.7)	0.0
Discount rate, benefit obligations	4.27%	4.81%
Equity-based compensation and employee benefits expense	$ 21.0	$ 24.4	26.6
Management
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Equity-based compensation and employee benefits expense	2.1	14.1	2.9
Performance Incentive Awards
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Performance and sales incentive expense	$ 11.7	$ 13.2	$ 13.9