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Future Policy Benefit Reserves - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
Insurance [Abstract] |  |  |  |  |
Liability for future policy benefit, expected future gross premium, discounted, before reinsurance | $ 3,491 |  | $ 3,491 |  | $ 3,546
Liability for future policy benefit, weighted-average duration | 11 years | 11 years | 11 years | 11 years |
Liability future policy benefit, losses recognized in current period | $ 14 | $ 24 | $ 28 | $ 44 |
Liability future policy benefit, losses recognized in prior period | $ 5 | $ 6 | $ 11 | $ 8 |

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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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- 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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