Investments (Net Investment Income - Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Net Investment Income [Line Items]
Net investment income	$ 1,269	$ 1,223
Trading securities (1)
Net Investment Income [Line Items]
Investment gains (losses) on trading securities still held	6	0
Other limited partnership interests
Net Investment Income [Line Items]
Net investment income	$ 56	$ 93

Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ 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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