Derivatives (Embedded Derivatives) (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Derivatives, Fair Value [Line Items]
Embedded derivatives within asset host contracts (2)	$ (46)	$ (53)
Embedded derivatives within liability host contracts (2)	(296)	(166)
Assumed affiliated reinsurance \| Other invested assets
Derivatives, Fair Value [Line Items]
Embedded derivatives within asset host contracts (2)	(49)	(22)
Assumed affiliated reinsurance \| Other Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Embedded derivatives within liability host contracts (2)	0	53
Fixed annuities with equity indexed returns [Member] \| Policyholder Account Balances [Member]
Derivatives, Fair Value [Line Items]
Embedded derivatives within liability host contracts (2)	140	67
Funds withheld and guarantees on reinsurance (including affiliated) \| Other Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Embedded derivatives within liability host contracts (2)	(353)	(281)
Funds withheld on affiliated reinsurance \| Other invested assets
Derivatives, Fair Value [Line Items]
Embedded derivatives within asset host contracts (2)	3	(31)
Funds withheld on unaffiliated reinsurance \| Other Noncurrent Liabilities
Derivatives, Fair Value [Line Items]
Embedded derivatives within liability host contracts (2)	$ (83)	$ (5)

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.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4B
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-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4B

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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-Name Accounting Standards Codification
-Section 50
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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