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Pension and Other Post-Retirement Benefits - Projected and Accumulated Benefit Obligations (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Defined Benefit Plan, Pension Plan with Project Benefit Obligation in Excess of Plan Assets [Abstract] |  |
Projected benefit obligations | $ 25.4 | $ 259.4
Fair value of plan assets | 0.0 | 227.3
Pension plans with an accumulated benefit obligation in excess of plan assets |  |
Accumulated benefit obligations | 22.0 | 22.8
Fair value of plan assets | $ 0.0 | $ 0.0

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- Definition Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Projected Fair Value of Plan Assets + References No definition available. + Details
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- Definition Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-3 + Details
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