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Retirement Benefits (Schedule of Assumptions Used) (Details) | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
DB Pension Plans |  |  |
Weighted average for net periodic benefit cost |  |  |
Expected long-term rate of return on plan assets | 7.50% | 7.20% | 6.50%
Actual rate of return on plan assets | 3.60% | 12.60% | (15.90%)
DB SERP |  |  |
Weighted average for benefit obligations |  |  |
Discount rate | 5.56% | 4.94% | 5.13%
Rate of compensation increase | 0.00% | 0.00% | 5.50%
Weighted average for net periodic benefit cost |  |  |
Service cost discount rate | 0.00% | 5.18% | 3.09%
Interest cost discount rate | 4.87% | 5.06% | 2.21%
Rate of compensation increase | 0.00% | 5.50% | 5.50%
OPEB Plan |  |  |
Weighted average for benefit obligations |  |  |
Discount rate | 5.69% | 5.02% | 5.21%
Weighted average for net periodic benefit cost |  |  |
Service cost discount rate | 5.12% | 5.31% | 3.23%
Interest cost discount rate | 4.91% | 5.10% | 2.45%
Expected long-term rate of return on plan assets | 7.50% | 7.20% | 6.50%
Pension Plan A | DB Pension Plans |  |  |
Weighted average for benefit obligations |  |  |
Discount rate | 5.73% | 5.05% | 5.24%
Rate of compensation increase | 3.70% | 3.60% | 3.60%
Weighted average for net periodic benefit cost |  |  |
Service cost discount rate | 5.08% | 5.27% | 3.09%
Interest cost discount rate | 4.93% | 5.12% | 2.44%
Rate of compensation increase | 3.60% | 3.60% | 3.60%
Pension Plan B | DB Pension Plans |  |  |
Weighted average for benefit obligations |  |  |
Discount rate | 5.59% | 4.95% | 5.14%
Weighted average for net periodic benefit cost |  |  |
Interest cost discount rate | 4.87% | 5.06% | 2.21%

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- Definition The interest rate used in calculating the interest cost of defined benefit plan net periodic benefit cost. + References No definition available. + Details
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- Definition The interest rate used in calculating the service cost of defined benefit plan net periodic benefit cost. + 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 rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost 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 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-8 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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