Investments (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Investments [Line Items]
Restricted assets in fixed maturities and short-term investments	$ 19,094	$ 17,945
Restricted assets in cash	213	261
Equity securities	10,377	9,151
Variable Interest Entity, Nonconsolidated, Comparison of Carrying Amount of Assets and Liabilities to Maximum Loss Exposure	159	97
Investments
Investments [Line Items]
Deferred Tax Assets, Valuation Allowance	189
Reserved alternative investment fund
Investments [Line Items]
Equity securities	$ 5,100	$ 5,000

[Line Items] for This table lists the investments. The line items identify information about all investments.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Amount of cash and cash equivalent restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

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Difference between the carrying amount of assets and liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the variable interest entity (VIE) and the reporting entity's maximum exposure to loss as a result of its involvement with the VIE, where the reporting entity is not the VIE's primary beneficiary.

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