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Retirement Plans and Other Employee Benefits - Schedule of Amounts Recognized in Other Comprehensive Income (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Pension Benefits |  |  |
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] |  |  |
Net actuarial (gain) loss arising during measurement period | $ 17 | $ 32 | $ 13
Items amortized during the measurement period: |  |  |
Net actuarial gain (loss) | (13) | (11) | (10)
Total recognized in other comprehensive income | 4 | 21 | 3
Other Benefits |  |  |
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] |  |  |
Net actuarial (gain) loss arising during measurement period | 0 | (3) | (7)
Items amortized during the measurement period: |  |  |
Net actuarial gain (loss) | 1 | 0 | 0
Total recognized in other comprehensive income | $ 1 | $ (3) | $ (7)

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- Definition Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (i-k) -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-11 Reference 3: 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 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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