Investments (Details) - Impairment Charges - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Investment Information
Fixed maturities credit impairment charges	$ 3	$ 26	$ 2
Total net impairment charges, including credit impairments, reported in net realized investment gains (losses) in the consolidated statement of income	12	38	2
Realized losses included in net realized investment gains (losses) related to real estate impairments	9	12
U.S. Treasury securities and obligations of U.S. government and government agencies and authorities [Member]
Investment Information
Fixed maturities credit impairment charges	0	12	0
Obligations of U.S. states, municipalities and political subdivisions [Member]
Investment Information
Fixed maturities credit impairment charges	1	14	0
Debt securities issued by foreign governments [Member]
Investment Information
Fixed maturities credit impairment charges	0	0	0
Mortgage-backed securities, collateralized mortgage obligations and pass-through securities [Member]
Investment Information
Fixed maturities credit impairment charges	0	0	0
Corporate and all other bonds [Member]
Investment Information
Fixed maturities credit impairment charges	$ 2	$ 0	$ 2

Total amount of credit impairment charges on debt securities included in net realized investment gains (losses) in the consolidated statement of income (loss).

No definition available.

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- Definition

Total amount of net impairment changes, including credit impairments, reported in net realized investment gains (losses) in the consolidated statement of income.

+ References

No definition available.

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- Definition

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482099/360-10-50-2

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(7)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(9)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-9

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