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Future Policy Benefit Reserves - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023
Insurance [Abstract] |  |
Liability for future policy benefit, expected future gross premium, discounted, before reinsurance | $ 3,664 | $ 4,046
Liability for future policy benefit, weighted-average duration | 11 years | 12 years
Liability future policy benefit, losses recognized in current period | $ 20 | $ 13
Liability future policy benefit, losses recognized in prior period | $ 2 | $ 11

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- Definition Liability For Future Policy Benefit, Losses Recognized In Current Period Reversed Due To Favorable Development + References No definition available. + Details
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- Definition Liability For Future Policy Benefit, Losses Recognized In Prior Period Reversed Due To Favorable Development + References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount, before effect of reinsurance, of discounted balance for expected future gross premium component of liability for future policy benefit. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-6 + Details
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- Definition Weighted-average duration of liability for future policy benefit, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (b)(5) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-6 + Details
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