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Annuity Reinsurance - Additional Information (Details) $ in Millions | 2 Months Ended | 3 Months Ended
--- | --- | ---
Mar. 31, 2026 USD ($) | Mar. 31, 2026 USD ($) contract | Mar. 31, 2025 USD ($)
Effects of Reinsurance [Line Items] |  |  |
Number of contracts | contract |  | 2 |
Interest accrual |  | $ 7 | $ 0
Annuity Reinsurance |  |  |
Effects of Reinsurance [Line Items] |  |  |
Interest accrual | $ 4 | $ 4 |

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- Definition Amount of interest expense for expected future policy benefit and expense component 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 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 13I -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-13I + Details
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