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Employee Benefit Plans (Actual & Target Allocation of Fair Value by Asset Class) (Details) - UNITED STATES | Dec. 31, 2023 | Dec. 31, 2022
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Pension Benefits |  |
Actual weighted average asset allocation by major asset class for the Invested Plans [Abstract] |  |
Actual | 100.00% | 100.00%
Pension Benefits | Fixed maturity securities AFS |  |
Actual weighted average asset allocation by major asset class for the Invested Plans [Abstract] |  |
Target | 85.00% |
Actual | 82.00% | 83.00%
Pension Benefits | Equity Securities |  |
Actual weighted average asset allocation by major asset class for the Invested Plans [Abstract] |  |
Target | 7.00% |
Actual | 6.00% | 6.00%
Pension Benefits | Alternative Securities |  |
Actual weighted average asset allocation by major asset class for the Invested Plans [Abstract] |  |
Target | 8.00% |
Actual | 12.00% | 11.00%
Other Postretirement Benefits |  |
Actual weighted average asset allocation by major asset class for the Invested Plans [Abstract] |  |
Actual | 100.00% | 100.00%
Other Postretirement Benefits | Fixed maturity securities AFS |  |
Actual weighted average asset allocation by major asset class for the Invested Plans [Abstract] |  |
Target | 95.00% |
Actual | 94.00% | 96.00%
Other Postretirement Benefits | Equity Securities |  |
Actual weighted average asset allocation by major asset class for the Invested Plans [Abstract] |  |
Target | 5.00% |
Actual | 6.00% | 4.00%
Other Postretirement Benefits | Alternative Securities |  |
Actual weighted average asset allocation by major asset class for the Invested Plans [Abstract] |  |
Target | 0.00% |
Actual | 0.00% | 0.00%

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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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- Definition Percentage of actual 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/2009/role/commonPracticeRef -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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