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Postretirement Benefits Other Than Pensions - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2024 USD ($) employees | Dec. 31, 2023 USD ($) | Dec. 31, 2019 USD ($)
Other Postretirement Benefit Plan, Defined Benefit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Number of retired employees covered | employees | 400 |  |
Number of active employees covered | employees | 500 |  |
Pre-tax reduction to its accumulated postretirement benefit obligation |  |  | $ 11.0
Amounts that will be amortized from AOCI in next fiscal Year |  | $ 2.1 |
Estimated future employer contributions in next fiscal year | $ 0.9 |  |
Medical Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Health care cost trend rate assumed for next fiscal year | 8.30% | 6.70% |
Health care cost trend rate assumed for future years | 4.70% | 4.70% |
Prescription Drug Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Health care cost trend rate assumed for next fiscal year | 12.30% | 8.00% |
Health care cost trend rate assumed for future years | 4.50% | 4.80% |

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- Definition Amount of cost (credit) included in accumulated other comprehensive (income) loss 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://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (l) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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