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Pension and Other Post-Retirement Benefits - Assumed Health Care Cost Trend Rates (Details) | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year, Post Age 65 | 6.00% | 6.25%
Medical Claims [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year, Pre Age 65 | 7.50% | 6.75%
Review of historical returns |  |
Rate to which the cost trend is expected to decline (the ultimate trend rate) | 4.50% | 4.50%
Year that rate reaches the ultimate trend rate | 2034 | 2033
Prescription Drugs Claims [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year, Pre Age 65 | 13.00% | 8.25%
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year, Post Age 65 | 12.00% | 8.25%
Review of historical returns |  |
Rate to which the cost trend is expected to decline (the ultimate trend rate) | 4.50% | 4.50%
Year that rate reaches the ultimate trend rate | 2034 | 2033
Medicare Advantage Part D |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year, Post Age 65 | 18.75% | 17.95%

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- Definition Ultimate trend rate for health care cost for defined benefit postretirement plan. + 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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