Pension and Postretirement Benefit Plans - Share of Expected Future Benefits Payments Schedule (Details) $ in Millions	Dec. 31, 2018 USD ($)
Schedule of Expected Future Pension Benefit Payment [Line Items]
2018	$ 2.4
Pension
Schedule of Expected Future Pension Benefit Payment [Line Items]
2018	17.7
2019	18.3
2020	18.9
2021	19.7
2022	20.8
2023 - 2027	120.3
Postretirement
Schedule of Expected Future Pension Benefit Payment [Line Items]
2018	2.3
2019	2.2
2020	2.1
2021	2.0
2022	1.9
2023 - 2027	$ 8.9

Schedule of Expected Future Pension Benefit Payment [Line Items]

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- Definition

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

+ References

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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