Investments - Realized Investment Gains and Losses and Change in Unrealized Investment Gains and Losses and Other Items (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Investment income:
Interest	$ 214	$ 173	$ 424	$ 342
Dividends	70	69	137	141
Other	5	4	12	11
Total	289	246	573	494
Less investment expenses	4	4	8	7
Total	285	242	565	487
Investment gains and losses, net
Other	5	6	12	26
Total	473	137	406	749
Equity securities
Investment gains and losses, net
Investment gains and losses on securities sold, net	(1)	7	(3)	4
Unrealized gains and losses on securities still held, net	481	142	411	747
Total	480	149	408	751
Fixed maturities
Investment gains and losses, net
Gross realized gains	1	4	1	4
Gross realized losses	0	(6)	0	(7)
Change in allowance for credit losses, net	(13)	(16)	(15)	(25)
Total	$ (12)	$ (18)	$ (14)	$ (28)

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Income derived from those other than interest and dividends.

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Amount of realized gain on 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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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 before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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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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