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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% |

X
- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (s) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (s) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(10) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Ultimate trend rate for health care cost for defined benefit postretirement plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Defined Benefit Plan, Assumptions Used in Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets, Percentage of Total Plan Assets + References No definition available. + Details
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- Definition Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year, Net Periodic Benefit Cost + References No definition available. + Details
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- Definition Amount of net gain (loss) recognized in net periodic benefit cost as a result of the purchase of nonparticipating annuity contracts to cover vested benefits. + References No definition available. + Details
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- Definition Number of Plan retirees and surviving beneficiaries affected by settlement. + References No definition available. + Details
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