v3.25.4

Retirement Benefits (Schedule of Assumptions Used) (Details) | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
DB Pension Plans |  |  |
Weighted average for net periodic benefit cost |  |  |
Expected long-term rate of return on plan assets | 7.30% | 7.50% | 7.20%
Actual rate of return on plan assets | 12.70% | 3.60% | 12.60%
DB SERP |  |  |
Weighted average for benefit obligations |  |  |
Discount rate | 5.22% | 5.56% | 4.94%
Weighted average for net periodic benefit cost |  |  |
Service cost discount rate | 0.00% | 0.00% | 5.18%
Interest cost discount rate | 5.29% | 4.87% | 5.06%
Rate of compensation increase | 0.00% | 0.00% | 5.50%
OPEB Plan |  |  |
Weighted average for benefit obligations |  |  |
Discount rate | 5.50% | 5.69% | 5.02%
Weighted average for net periodic benefit cost |  |  |
Service cost discount rate | 5.85% | 5.12% | 5.31%
Interest cost discount rate | 5.39% | 4.91% | 5.10%
Expected long-term rate of return on plan assets | 7.15% | 7.50% | 7.20%
Pension Plan A | DB Pension Plans |  |  |
Weighted average for benefit obligations |  |  |
Discount rate | 5.58% | 5.73% | 5.05%
Rate of compensation increase | 3.70% | 3.70% | 3.60%
Weighted average for net periodic benefit cost |  |  |
Service cost discount rate | 5.77% | 5.08% | 5.27%
Interest cost discount rate | 5.43% | 4.93% | 5.12%
Rate of compensation increase | 3.70% | 3.60% | 3.60%
Pension Plan B | DB Pension Plans |  |  |
Weighted average for benefit obligations |  |  |
Discount rate | 5.28% | 5.59% | 4.95%
Weighted average for net periodic benefit cost |  |  |
Interest cost discount rate | 5.30% | 4.87% | 5.06%

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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 5 -Subparagraph (j)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-5 Reference 2: 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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