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Annuity Reinsurance - Range of Guaranteed Minimum Credit Rating (Details) - USD ($) $ in Millions | Mar. 31, 2026 | Dec. 31, 2025
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Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items] |  |
Policyholder account balances for annuity reinsurance contracts | $ 263 | $ 0
Policyholder Account Balance, at Guaranteed Minimum Crediting Rate |  |
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items] |  |
Policyholder account balances for annuity reinsurance contracts | $ 263 |
4.00% - 5.00% | Minimum |  |
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items] |  |
Range of Guaranteed Minimum Crediting Rate | 4.00% |
4.00% - 5.00% | Maximum |  |
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items] |  |
Range of Guaranteed Minimum Crediting Rate | 5.00% |
4.00% - 5.00% | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate |  |
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items] |  |
Policyholder account balances for annuity reinsurance contracts | $ 12 |
5.00% - 6.00% | Minimum |  |
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items] |  |
Range of Guaranteed Minimum Crediting Rate | 5.00% |
5.00% - 6.00% | Maximum |  |
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items] |  |
Range of Guaranteed Minimum Crediting Rate | 6.00% |
5.00% - 6.00% | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate |  |
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items] |  |
Policyholder account balances for annuity reinsurance contracts | $ 251 |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 29F -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-29F Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-7A + Details
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- Definition Amount due to policyholder. Includes, but is not limited to, unpaid policy dividend, retrospective refund, and undistributed earnings on participating business. Excludes future policy benefit and claim expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-7A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-7A Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(14)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 29F -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-29F Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-7A + Details
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