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Postretirement Benefits - Asset Allocation (Details) - Employee Pension Plan | Dec. 31, 2024 | Dec. 31, 2023
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Target asset allocation for the portfolio: |  |
Total plan assets | 100.00% | 100.00%
Actual asset allocation for the portfolio: |  |
Total plan assets | 100.00% | 100.00%
Total equity securities |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 35.00% | 45.00%
Actual asset allocation for the portfolio: |  |
Total plan assets | 35.00% | 45.00%
U.S. equity securities |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 21.00% | 27.00%
Actual asset allocation for the portfolio: |  |
Total plan assets | 21.00% | 26.00%
U.S. small capitalization core equity |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 100.00% |
Non-U.S. equity securities |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 14.00% | 18.00%
Actual asset allocation for the portfolio: |  |
Total plan assets | 14.00% | 19.00%
International small capitalization risk controlled equity |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 11.00% |
International emerging markets equity |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 20.00% |
International risk controlled equity |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 69.00% |
Debt securities |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 64.00% | 54.00%
Actual asset allocation for the portfolio: |  |
Total plan assets | 63.00% | 54.00%
U.S. Treasury Strips |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 59.00% |
U.S. corporate bonds with an emphasis on long duration bonds rated A or better |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 41.00% |
Other |  |
Target asset allocation for the portfolio: |  |
Total plan assets | 1.00% | 1.00%
Actual asset allocation for the portfolio: |  |
Total plan assets | 2.00% | 1.00%

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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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