Schedule I Summary of Investments - Other Than Investments in Affiliates (Details) $ in Millions	Dec. 31, 2021 USD ($)
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	$ 55,714
Amount at which shown on Balance Sheet	57,749
U.S. government and government agencies and authorities (guaranteed and sponsored)
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	5,706
Fair Value	5,881
Amount at which shown on Balance Sheet	5,881
States, municipalities and political subdivisions
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	7,473
Fair Value	8,257
Amount at which shown on Balance Sheet	8,257
Foreign government/government agencies
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	883
Fair Value	910
Amount at which shown on Balance Sheet	910
Public utilities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	1,917
Fair Value	2,050
Amount at which shown on Balance Sheet	2,050
All other corporate bonds
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	15,827
Fair Value	16,657
Amount at which shown on Balance Sheet	16,657
Industrial, miscellaneous and all other
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	1,509
Fair Value	1,509
Amount at which shown on Balance Sheet	1,509
Non-redeemable preferred stocks
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	585
Fair Value	585
Amount at which shown on Balance Sheet	585
Equity securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	2,094
Fair Value	2,094
Amount at which shown on Balance Sheet	2,094
Mortgage loans [1]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Fair Value	5,576
Amount at which shown on Balance Sheet	5,383
Other investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	370
Fair Value	375
Amount at which shown on Balance Sheet	375
Short-term investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	3,697
Fair Value	3,697
Amount at which shown on Balance Sheet	3,697
Investments in partnerships and trusts
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	3,353
Amount at which shown on Balance Sheet	3,353
All other mortgage-backed and asset-backed securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	8,982
Fair Value	9,092
Amount at which shown on Balance Sheet	9,092
Total fixed maturities, available-for-sale
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	40,788
Fair Value	42,847
Amount at which shown on Balance Sheet	$ 42,847

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Amount of investment held by insurance company, excluding investment in related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 7
-Subparagraph (SX 210.12-15(Column D))
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Cost of investment held by insurance company, excluding investment in related party.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 7
-Subparagraph (SX 210.12-15(Column B))
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-SubTopic 320
-Section S99
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-Subparagraph (SX 210.12-15(Column C))
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