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Retirement Plans and Other Employee Benefits - Narrative (Details) | 12 Months Ended
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Dec. 31, 2021 USD ($) pensionPlan | Dec. 31, 2020 USD ($) | Dec. 31, 2019 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 | $ 10,000,000 | $ 4,000,000 |
Number of plans affected by interest credit ratings | pensionPlan | 1 |  |
Funded status of the plans | $ 4,000,000 | 3,000,000 |
Qualified pension | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Estimated social security benefits age | 65 years |  |
Employer contributions | $ 6,000,000 | 0 | $ 0
Funded status of the plans | 37,000,000 | 41,000,000 |
Flexible Benefits Contribution |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | 51,000,000 | $ 37,000,000 | $ 28,000,000
Nonqualified pension | Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | 5,000,000 |  |
Expected pension contribution | $ 5,000,000 |  |
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 |  |
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% |  |

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- Definition Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Return Time Horizon + References No definition available. + Details
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- Definition Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Assumptions Term + References No definition available. + Details
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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 Age in which estimates of social security benefits received will be incorporated for purpose of determining pension benefits. + 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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- Definition Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123453770&loc=d3e1703-114919 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 + Details
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