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Benefit Plans (Components of Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Defined Benefit Plan, Net Period Benefit Cost (Credit) [Abstract] |  |  |
Service cost | $ 10.8 | $ 10.4 |
Curtailment | 0.0 | 0.0 | $ 2.1
Net periodic benefit cost | 4.1 | 7.3 |
Pension Plan [Member] |  |  |
Defined Benefit Plan, Net Period Benefit Cost (Credit) [Abstract] |  |  |
Service cost | 10.8 | 10.4 | 10.2
Interest cost | 9.4 | 9.8 | 10.5
Expected return on assets | (15.7) | (13.5) | (12.6)
Amortization of prior service credit | (1.3) | (1.3) | (1.4)
Amortization of transition obligation | 0.0 | 0.0 | 0.1
Amortization of actuarial loss (gain) | 3.8 | 4.9 | 4.8
Curtailment | 0.0 | 0.0 | 2.1
Net periodic benefit cost | 7.0 | 10.3 | 9.5
Other changes in plan assets and benefit obligations recognized in OCI, pre-tax: |  |  |
Net loss (gain) arising during period | 3.5 | (9.0) | 19.2
Prior service credit arising during period | 0.3 | 0.0 | 0.0
Amortization of prior service credit | 1.3 | 1.3 | 1.4
Amortization of transition obligation | 0.0 | 0.0 | (0.1)
Amortization of actuarial (loss) gain | (3.8) | (4.9) | (4.8)
Curtailment | 0.0 | 0.0 | (3.1)
Foreign currency translation | (1.2) | 2.6 | (3.2)
Total recognized in OCI | 0.1 | (10.0) | 9.4
Total recognized in net periodic benefit cost and OCI | 7.1 | 0.3 | 18.9
Other Postretirement Benefits Plan [Member] |  |  |
Defined Benefit Plan, Net Period Benefit Cost (Credit) [Abstract] |  |  |
Service cost | 0.0 | 0.0 | 0.5
Interest cost | 0.2 | 0.3 | 0.5
Expected return on assets | 0.0 | 0.0 | 0.0
Amortization of prior service credit | (0.7) | (0.7) | 0.0
Amortization of transition obligation | 0.0 | 0.0 | 0.0
Amortization of actuarial loss (gain) | (2.4) | (2.6) | (1.4)
Curtailment | 0.0 | 0.0 | 0.0
Net periodic benefit cost | (2.9) | (3.0) | (0.4)
Other changes in plan assets and benefit obligations recognized in OCI, pre-tax: |  |  |
Net loss (gain) arising during period | (1.4) | (1.1) | (0.1)
Prior service credit arising during period | 0.0 | 0.0 | (3.0)
Amortization of prior service credit | 0.7 | 0.7 | 0.0
Amortization of transition obligation | 0.0 | 0.0 | 0.0
Amortization of actuarial (loss) gain | 2.4 | 2.6 | 1.4
Curtailment | 0.0 | 0.0 | 0.0
Foreign currency translation | 0.0 | 0.0 | 0.0
Total recognized in OCI | 1.7 | 2.2 | (1.7)
Total recognized in net periodic benefit cost and OCI | (1.2) | (0.8) | (2.1)
Domestic Plan [Member] | Pension Plan [Member] |  |  |
Defined Benefit Plan, Net Period Benefit Cost (Credit) [Abstract] |  |  |
Net periodic benefit cost | 4.8 | 7.3 | 7.1
Domestic Plan [Member] | Other Postretirement Benefits Plan [Member] |  |  |
Defined Benefit Plan, Net Period Benefit Cost (Credit) [Abstract] |  |  |
Net periodic benefit cost | (2.9) | (3.0) | (0.4)
Foreign Plan [Member] | Pension Plan [Member] |  |  |
Defined Benefit Plan, Net Period Benefit Cost (Credit) [Abstract] |  |  |
Net periodic benefit cost | 2.2 | 3.0 | 2.4
Foreign Plan [Member] | Other Postretirement Benefits Plan [Member] |  |  |
Defined Benefit Plan, Net Period Benefit Cost (Credit) [Abstract] |  |  |
Net periodic benefit cost | $ 0.0 | $ 0.0 | $ 0.0

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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(5) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(5) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + Details
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + Details
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(7) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + Details
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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