Investments (Details) - Net Investment Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net investment income
Gross investment income	$ 3,073	$ 2,264	$ 2,508
Investment expenses	40	37	40
Net investment income	3,033	2,227	2,468
Fixed maturities [Member]
Net investment income
Gross investment income	1,989	2,011	2,070
Equity securities [Member]
Net investment income
Gross investment income	19	15	15
Short-term securities [Member]
Net investment income
Gross investment income	7	44	105
Real estate [Member]
Net investment income
Gross investment income	59	48	55
Other investments [Member]
Net investment income
Gross investment income	$ 999	$ 146	$ 263

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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