Employee Benefits (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
General Discussion of Pension and Other Postretirement Benefits [Abstract]
Number of Participants Domestic Pension Plan	3,600
Number of Participants Postretirement Benefit Plan	1,800
Deferred Compensation Arrangements [Abstract]
Deferred Compensation Liability	$ 92.4	$ 95.7
Deferred Compensation Expense	9.7	6.3	$ 9.8
Deferred Benefit Liability	129.1	141.5
Deferred Benefit Expense	8.8	9.7	$ 10.8
Cash Surrender Value of Life Insurance	171.5	167.0
Deferred Compensation Plan Assets	12.9	10.7
Supplemental Unemployment Benefits [Abstract]
Health and Life Insurance Benefit Obligation	8.2	$ 8.0
Income Replacement Benefit Obligation	0.0
Pre-tax net actuarial loss, re-measurement of the benefit obligation	$ 79.0