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]
Gross investment income	$ 450	$ 607	$ 915	$ 1,128
Investment expense	(18)	(16)	(35)	(33)
Net investment income	432	591	880	1,095
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	441	425	870	853
Equity securities
Net Investment Income [Line Items]
Gross investment income	(11)	20	(9)	49
Limited partnership investments
Net Investment Income [Line Items]
Gross investment income	6	146	24	189
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	12	15	27	29
Short term investments
Net Investment Income [Line Items]
Gross investment income	2	0	2	0
Trading portfolio
Net Investment Income [Line Items]
Gross investment income	0	2	1	7
Other
Net Investment Income [Line Items]
Gross investment income	$ 0	$ (1)	$ 0	$ 1

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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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