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Postretirement Benefits Other Than Pensions - Actuarial Assumptions of OPEB Expense (Details) | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items] |  |  |
Effective Rate for Interest on Service Cost | 4.85% | 5.04% | 2.54%
Other Postretirement Benefit Plan, Defined Benefit |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Weighted-average Discount Rate | 4.92% | 5.11% | 2.56%
Service Cost Discount Rate | 4.94% | 5.12% | 2.79%
Interest Cost Discount Rate | 4.85% | 5.03% | 1.97%
Rate of Increase in Future Compensation Levels | 2.20% | 2.20% | 2.20%

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- Definition Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Interest Cost Discount Rate + 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 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 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 of compensation increase used to determine net periodic benefit cost 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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