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Retirement Benefits (Assumptions Used To Determine Benefit Obligations) (Details) | 12 Months Ended |
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Discount rate at measurement date | 5.70% | 5.25% |
Increase in future compensation | 4.00% | 3.50% |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Weighted-Average Interest Crediting Rate | 5.50% | 5.50% |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase for 2024 |  | 4.00% |
Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Discount rate at measurement date | 5.70% | 5.25% |
Increase in future compensation | 4.00% | 3.50% |
Medical cost trend rate (ultimate) | 5.00% | 5.00% | 5.00%
Medical cost trend rate (initial) |  |  | 5.00%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase for 2024 |  | 4.00% |
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year, Pre-Medicare Plan Participantes | 7.00% | 6.93% |
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year, Post-Medicare Plan Participants | 7.00% | 6.50% |
Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate | 2033 | 2030 |
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year, Post-Medicare Plan Participants Adjustment | 3.00% | 3.00% |
Postretirement Health Coverage |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Medical cost trend rate (ultimate) | 2.50% | 2.50% | 3.00%
Medical cost trend rate (initial) | 2.50% | 2.50% |

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- Definition Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase for 2024 + References No definition available. + Details
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- Definition Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year, Post-Medicare Plan Participants + References No definition available. + Details
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- Definition Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year, Post-Medicare Plan Participants Adjustment + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted-average interest crediting rate used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, cash balance and other defined benefit plans with promised interest crediting rate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(4) -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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- 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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