Pensions and Other Postretirement Benefits - Amounts in Accumulated Other Comprehensive Loss to be Recognized (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Forecast
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined Benefit Plan, Benefit Obligation, NonCash Settlement	$ 150.0
Defined Benefit Plan, Benefit Obligation, Transfer To Annuity Contract	$ 750.0
Pension Benefit Plans
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Recognition of Prior Service Cost		$ 0.2
Recognition of Actuarial Loss (Gain)(a)		4.9
Posretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Recognition of Prior Service Cost		(0.3)
Recognition of Actuarial Loss (Gain)(a)		$ (2.1)

Defined Benefit Plan, Benefit Obligation, NonCash Settlement

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- Definition

Defined Benefit Plan, Benefit Obligation, Transfer To Annuity Contract

+ References

No definition available.

+ Details

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- Definition

Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

+ 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 (s)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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