Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Net Investment Income [Line Items]
Less: Investment expenses	$ 242	$ 237
Net investment income	4,284	5,314
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	5,025	5,344
Net investment income	4,783	5,107
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	2,714	2,753
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	7	11
FVO Securities
Net Investment Income [Line Items]
Net investment income	(65)	36
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	824	863
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	116	121
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	328	176
Other limited partnership interests
Net Investment Income [Line Items]
Gross Investment Income, Operating	926	1,282
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	31	25
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	18	23
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	126	54
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ (499)	$ 207

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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