Benefit Plans (Textuals) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 239.5	$ 192.4
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment	0.0	(2.1)	$ 0.0
Pension settlement charge	0.0	0.0	50.4
401 (k) plan contributions	5.7	4.9	4.8
Accumulated benefit obligation	283.7	258.4
Expected contribution to the plan	$ 1.8
Assumed healthcare cost trend rate, benefit obligation	6.60%
Ultimate healthcare cost trend rate, benefit obligation	5.00%
Effect of one percentage point increase on benefit obligation	$ 0.1
Effect of one percentage point decrease on benefit obligation	$ 0.1
Assumed healthcare cost trend rate, net periodic benefit cost	6.60%
Ultimate healthcare cost trend rate, net periodic benefit cost	5.00%
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Annuity Purchase			47.0
Settlement			$ 139.4
Number of Employees & Beneficiaries Affected by Settlement			1,750
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 34.7	28.8
Accumulated benefit obligation	67.3	$ 60.6
Expected contribution to the plan	$ 0.9
Discount rate	1.62%	2.25%
Rate of compensation increase	2.44%	2.59%
Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.65%	4.15%
Rate of compensation increase	4.25%
Percentage of global plan assets	87.00%
Long-term rate of return on assets	7.00%	7.25%	7.25%
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 239.5	$ 192.4	$ 188.9
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment	0.0	(2.1)	0.0
Pension settlement charge	0.0	$ 0.0	$ 50.4
Actuarial net loss that will be amortized from accumulated other comprehensive loss	3.8
Prior service credit that will be amortized from accumulated other comprehensive loss	$ 1.4
Discount rate	3.14%	3.68%
Rate of compensation increase	3.80%	4.04%
Long-term rate of return on assets	6.47%	6.95%	6.84%
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 0.0	$ 0.0	$ 0.0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment	0.0	0.0	0.0
Pension settlement charge	0.0	$ 0.0	$ 0.0
Actuarial net loss that will be amortized from accumulated other comprehensive loss	2.1
Prior service credit that will be amortized from accumulated other comprehensive loss	0.7
Expected contribution to the plan	$ 0.7
Discount rate	3.45%	3.90%