Investments - Pledged Investments (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities collateral pledged to us	$ 2,257	$ 2,853
Carrying value of reverse repurchase agreements	2,200	2,800
Total carrying values of cash and securities deposited under requirements of regulatory authorities or other insurance-related arrangements	7,900	7,800
Federal Home Loan Bank stock	13	13
Bonds available for sale and short-term investments held in escrow	73	73
Asset Pledged as Collateral
Financial Instruments Owned and Pledged as Collateral [Line Items]
Fixed maturity securities available for sale	$ 1,800	$ 1,600

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

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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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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This element represents the current portion of investments which are not defined as or included in marketable (debt, equity, or other) securities that are pledged or subject to withdrawal restrictions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The carrying value of securities purchased to be resold in reverse repurchase transactions as of the balance sheet date.

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No definition available.

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The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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