Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Net Investment Income [Line Items]
Less: Investment expenses	$ 461	$ 242
Net investment income	4,645	4,284
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	4,802	5,025
Net investment income	4,341	4,783
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	3,139	2,714
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	12	7
FVO Securities
Net Investment Income [Line Items]
Net investment income	48	(65)
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	1,041	824
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	119	116
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	26	328
Other limited partnership interests
Net Investment Income [Line Items]
Gross Investment Income, Operating	25	926
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	217	31
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	19	18
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	156	126
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ 304	$ (499)

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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-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2)
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 944
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-Section S99
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+ References

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