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Employee Benefits - Weighted Average Assumption (Details) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Pension Plan |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Discount rate | 4.90% | 2.60% | 2.20%
Expected rate of return on plan assets | 6.30% | 6.00% | 6.30%
Post-Retirement Health and Welfare Benefits |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |
Discount rate | 4.80% | 2.30% | 2.00%
Current medical trend rate | 650.00% | 650.00% | 650.00%
Ultimate trend rate | 500.00% | 500.00% | 500.00%
Year when ultimate trend rate will be reached | 2029 | 2028 | 2027

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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 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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