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Retirement Plans and Other Employee Benefits - Narrative (Details) | 12 Months Ended
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Dec. 31, 2023 USD ($) pensionPlan | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |
Minimum required outstanding par value to each issue of bonds | $ 300,000,000 |  |
Threshold amortization percentage of projected benefit obligation | 10.00% |  |
Threshold amortization, percentage of market-related value of plan assets | 10.00% |  |
Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | $ 3,000,000 | $ 3,000,000 |
Number of plans affected by interest credit ratings | pensionPlan | 1 |  |
Funded status of the plans | $ (37,000,000) | (22,000,000) |
Savings Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer investment in qualified defined contribution plan | 100.00% |  |
Maximum percent of employee pre-tax contributions that may be matched by the Company (percent) | 6.00% |  |
Qualified pension | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Estimated social security benefits age | 65 years |  |
Employer contributions | $ 0 | 0 | $ 6,000,000
Funded status of the plans | (13,000,000) | 4,000,000 |
Nonqualified pension | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | 6,000,000 |  |
Expected pension contribution | 5,000,000 |  |
Flexible Benefits Contribution |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | $ 48,000,000 | $ 47,000,000 | $ 51,000,000
Qualified pension/ postretirement benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expected time horizon | 30 years |  |
Qualified pension/ postretirement benefits | Maximum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Term used for assumption calculation | 30 years |  |

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- Definition Defined Benefit Plan, Number Of Plans Affected By Interest Credit Ratings + References No definition available. + Details
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- Definition Percent of a market-related value of the plan assets at the beginning of the year used to determine the threshold calculated under the minimum amortization method. Threshold is calculated as the greater of some percent of the plan's projected benefit obligation or a percent of the market-related value of plan assets at the beginning of the year. + References No definition available. + Details
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- Definition Percent of a plan's projected benefit obligation used to determine the threshold calculated under the minimum amortization method. Threshold is calculated as the greater of some percent of the plan's projected benefit obligation or some percent of the market-related value of plan assets at the beginning of the year. + References No definition available. + Details
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