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Retirement Benefits (Target Allocation Of The Plans' Asset Categories) (Details) | Dec. 31, 2023 | Dec. 31, 2022
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Pension Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 100.00% | 100.00%
Pension Benefits | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 1.00% | 1.00%
Pension Benefits | Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 51.00% | 51.00%
Pension Benefits | U.S. large-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 15.00% | 15.00%
Pension Benefits | U.S. small- and mid-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 8.00% | 8.00%
Pension Benefits | Global |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 16.00% | 12.00%
Pension Benefits | International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 12.00% | 16.00%
Pension Benefits | Debt securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 35.00% | 35.00%
Pension Benefits | Diversified credit |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 7.00% | 7.00%
Pension Benefits | Real estate |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 6.00% | 6.00%
Pension Benefits | Private equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 1.00% | 1.00%
Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 100.00% | 100.00%
Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 1.00% | 2.00%
Postretirement Benefits | Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 63.00% | 60.00%
Postretirement Benefits | U.S. large-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 32.00% | 29.00%
Postretirement Benefits | U.S. small- and mid-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 8.00% | 8.00%
Postretirement Benefits | Global |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 15.00% | 10.00%
Postretirement Benefits | International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 8.00% | 13.00%
Postretirement Benefits | Debt securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of Plan Assets at December 31, | 36.00% | 38.00%
Minimum | Pension Benefits | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% |
Minimum | Pension Benefits | Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 45.00% |
Minimum | Pension Benefits | U.S. large-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 11.00% |
Minimum | Pension Benefits | U.S. small- and mid-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 3.00% |
Minimum | Pension Benefits | Global |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 10.00% |
Minimum | Pension Benefits | International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 6.00% |
Minimum | Pension Benefits | Debt securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 35.00% |
Minimum | Pension Benefits | Diversified credit |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% |
Minimum | Pension Benefits | Real estate |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% |
Minimum | Pension Benefits | Private equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% |
Minimum | Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% |
Minimum | Postretirement Benefits | Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 55.00% |
Minimum | Postretirement Benefits | U.S. large-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 23.00% |
Minimum | Postretirement Benefits | U.S. small- and mid-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 3.00% |
Minimum | Postretirement Benefits | Global |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 9.00% |
Minimum | Postretirement Benefits | International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 5.00% |
Minimum | Postretirement Benefits | Debt securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 33.00% |
Maximum | Pension Benefits | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 5.00% |
Maximum | Pension Benefits | Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 55.00% |
Maximum | Pension Benefits | U.S. large-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 21.00% |
Maximum | Pension Benefits | U.S. small- and mid-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 13.00% |
Maximum | Pension Benefits | Global |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 20.00% |
Maximum | Pension Benefits | International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 16.00% |
Maximum | Pension Benefits | Debt securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 45.00% |
Maximum | Pension Benefits | Diversified credit |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 10.00% |
Maximum | Pension Benefits | Real estate |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 10.00% |
Maximum | Pension Benefits | Private equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 5.00% |
Maximum | Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 7.00% |
Maximum | Postretirement Benefits | Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 65.00% |
Maximum | Postretirement Benefits | U.S. large-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 33.00% |
Maximum | Postretirement Benefits | U.S. small- and mid-capitalization |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 13.00% |
Maximum | Postretirement Benefits | Global |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 19.00% |
Maximum | Postretirement Benefits | International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 15.00% |
Maximum | Postretirement Benefits | Debt securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 43.00% |

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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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