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Annuity Reinsurance - Future Policy Benefits for Annuity Reinsurance Contracts (Details) - USD ($) $ in Millions | Mar. 31, 2026 | Dec. 31, 2025
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Effects of Reinsurance [Line Items] |  |
Future policy benefits for annuity reinsurance contracts | $ 475 | $ 0
Annuity Reinsurance |  |
Effects of Reinsurance [Line Items] |  |
Future policy benefits for annuity reinsurance contracts | 447 |
Deferred Profit Liability |  |
Effects of Reinsurance [Line Items] |  |
Future policy benefits for annuity reinsurance contracts | $ 28 |

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- Definition Amount, after effect of reinsurance, of liability for future policy benefit. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-6 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 29E -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-29E Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Subparagraph (g)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480016/944-40-65-2 + Details
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