Pensions and Other Postretirement Benefits - Expected Benefit Payments (Details) $ in Millions	Dec. 31, 2019 USD ($)
Pension Benefit Plans
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
2020	$ 71.4
2021	73.0
2022	74.5
2023	75.9
2024	76.9
2025 - 2029	384.5
Posretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
2020	2.4
2021	2.5
2022	2.6
2023	2.6
2024	2.8
2025 - 2029	$ 11.4

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

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=118255775&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 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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