Retirement Benefits Plans (Components of the Changes in Benefit Obligations and Fair Value of Plan Assets) (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Change in Benefit Obligation | |||
| Current portion of retirement liabilities classified in accrued liabilities | $ 3.0 | $ 3.1 | |
| Postretirement benefit plans | |||
| Change in Benefit Obligation | |||
| Benefit obligations at beginning of year | 31.3 | 32.3 | |
| Interest cost | 1.0 | 1.1 | $ 1.3 |
| Actuarial (gain)/loss | (0.8) | 1.1 | |
| Benefits paid | (3.3) | (3.2) | |
| Benefit obligations at end of year | 28.2 | 31.3 | 32.3 |
| Prior service (cost) benefit | $ 0.0 | $ 0.0 | $ 1.5 |
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- Definition Other comprehensive income defined benefit plan net prior service benefit credit arising during period net of tax. No definition available.
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- Definition Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of liability, recognized in statement of financial position, for pension, other postretirement and postemployment benefits, classified as current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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