Benefit Plans (Textuals) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 214.5	$ 239.5
Pension curtailment gain	0.0	0.0	$ (2.1)
401 (k) plan contributions	6.5	5.7	$ 4.9
Accumulated benefit obligation	263.0	283.7
Expected contribution to the plan	$ 3.2
Assumed healthcare cost trend rate, benefit obligation	6.25%
Ultimate healthcare cost trend rate, benefit obligation	5.00%
Assumed healthcare cost trend rate, net periodic benefit cost	6.60%
Ultimate healthcare cost trend rate, net periodic benefit cost	5.00%
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 33.4	34.7
Accumulated benefit obligation	64.0	$ 67.3
Expected contribution to the plan	$ 2.3
Discount rate	2.19%	1.62%
Rate of compensation increase	2.60%	2.44%
Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.30%	3.65%
Rate of compensation increase	4.25%	4.25%
Percentage of global plan assets	84.45%
Long-term rate of return on assets	7.00%	7.00%	7.25%
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 214.5	$ 239.5	$ 192.4
Pension curtailment gain	0.0	$ 0.0	$ (2.1)
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	$ 0.1
Discount rate	3.76%	3.14%
Rate of compensation increase	4.01%	3.80%
Long-term rate of return on assets	6.71%	6.47%	6.95%
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0.0	$ 0.0	$ 0.0
Pension curtailment gain	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	4.20%	3.45%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation	30.00%	65.00%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation	70.00%	35.00%

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

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Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

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Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Ultimate trend rate for health care cost for defined benefit postretirement plan.

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Amount of cost for defined contribution plan.

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