Investments (Details) - Net Investment Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net investment income
Gross investment income	$ 2,605	$ 3,073	$ 2,264
Investment expenses	43	40	37
Net investment income	2,562	3,033	2,227
Fixed maturities [Member]
Net investment income
Gross investment income	2,113	1,989	2,011
Equity securities [Member]
Net investment income
Gross investment income	17	19	15
Short-term securities [Member]
Net investment income
Gross investment income	73	7	44
Real estate [Member]
Net investment income
Gross investment income	66	59	48
Other investments [Member]
Net investment income
Gross investment income	$ 336	$ 999	$ 146

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.

+ References

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