Pension and Other Postretirement Benefits - Future Benefit Payments (Details) $ in Millions	Dec. 31, 2017 USD ($)
Pension Benefits
Future service benefit payments
2018	$ 22.7
2019	24.4
2020	21.7
2021	23.4
2022	23.3
Years 2023-2027	128.1
Postretirement Benefits Other than Pensions
Future service benefit payments
2018	5.3
2019	4.3
2020	4.6
2021	4.9
2022	4.8
Years 2023-2027	$ 18.1

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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.

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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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