Investments - Realized Investment Gains and Losses and Change in Unrealized Investment Gains and Losses and Other Items (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Investment income:
Interest	$ 210	$ 169
Dividends	67	72
Other	7	7
Total	284	248
Less investment expenses	4	3
Total	280	245
Investment gains and losses, net
Other	7	20
Total	(67)	612
Equity securities
Investment gains and losses, net
Investment gains and losses on securities sold, net	(1)	(11)
Unrealized gains and losses on securities still held, net	(71)	613
Total	(72)	602
Fixed maturities
Investment gains and losses, net
Gross realized losses	0	(1)
Change in allowance for credit losses, net	(2)	(9)
Total	$ (2)	$ (10)

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Income derived from those other than interest and dividends.

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

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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 of realized gain (loss) on investment.

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Amount of unrealized gain (loss) on investment.

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