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	$ 1,093	$ 1,231	$ 2,269	$ 2,434
Less: Investment expenses	49	35	90	69
Net investment income	1,044	1,196	2,179	2,365
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	733	694	1,442	1,374
Equity securities
Net Investment Income [Line Items]
Gross investment income	1	1	1	2
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	205	166	407	329
Policy loans
Net Investment Income [Line Items]
Gross investment income	12	11	21	21
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	122	350	363	688
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	4	1	5	2
Other
Net Investment Income [Line Items]
Gross investment income	$ 16	$ 8	$ 30	$ 18

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, 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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