Investments - Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Net Investment Income [Line Items]
Investment income, operating	$ 388	$ 634	$ 839	$ 1,204
Investment expenses	(22)	(18)	(41)	(38)
Net investment income	366	616	798	1,166
Net investment income recognized	(95)	28	(120)	58
Fixed maturity securities
Net Investment Income [Line Items]
Investment income, operating	441	425	870	853
Limited partnership investments
Net Investment Income [Line Items]
Gain (losses) on investments, before investment expenses	7	149	27	196
Equity securities
Net Investment Income [Line Items]
Gain (losses) on investments, before investment expenses	(11)	20	(9)	49
Income (loss) from trading portfolio
Net Investment Income [Line Items]
Gain (losses) on investments, before investment expenses	(62)	26	(77)	76
Other
Net Investment Income [Line Items]
Investment income, operating	$ 13	$ 14	$ 28	$ 30

Amount, before investment expenses, of gains (losses) on investments.

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Trading Securities, Change in Unrealized Holding Gain (Loss), Net Investment Income Recognized

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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 of expenses related to the generation of investment income.

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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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