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Retirement and Postretirement Plans - Amounts Recognized in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Pension |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Unrecognized prior service (benefit) cost | $ 10.3 | $ 11.6
Pension | United States of America | Bargaining Plan |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Unrecognized prior service (benefit) cost | 9.9 | 11.1
Pension | United Kingdom | Pension Scheme |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Unrecognized prior service (benefit) cost | 0.4 | 0.5
Postretirement |  |
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Unrecognized prior service (benefit) cost | $ (38.0) | $ (44.0)

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- Definition Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-14A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (j) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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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. + Details
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