Variable Interest Entities (Details) - Variable Interest Entities - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Variable Interest Entity [Line Items]
Net investment income	$ 23	$ 92	$ 134	$ 249
Investment related gains (losses)	645	565	1,711	1,583
Other Nonoperating Gains (Losses)	40	30
Other gains (losses), net			42	47
Mortgage loans
Variable Interest Entity [Line Items]
Investment related gains (losses)	2	8	8	15
Investment funds
Variable Interest Entity [Line Items]
Investment related gains (losses)	615	521	1,714	1,509
Trading securities
Variable Interest Entity [Line Items]
Investment revenue	(16)	(54)	(96)	(155)
Investment related gains (losses)	(12)	6	(53)	12
Mortgage loans
Variable Interest Entity [Line Items]
Investment revenue	(22)	(41)	(79)	(122)
Investment funds
Variable Interest Entity [Line Items]
Investment expenses	0	7	6	28
Other Investments
Variable Interest Entity [Line Items]
Investment expenses	$ (15)	$ (10)	$ (47)	$ (56)

Investment Funds Gain (Loss)

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Amount of realized and unrealized gain (loss) on investment.

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Amount of gain (loss) included in earnings for investments classified as other.

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Amount, before 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.

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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.

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