Investments (Details) - Impairment Charges - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Investment Information
Fixed maturities credit impairment charges	$ 5	$ 3	$ 26
Total net impairment charges, including credit impairments, reported in net realized investment losses in the consolidated statement of income	10	12	38
Realized losses included in net realized investment losses related to real estate impairments	5	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	0	12
Obligations of U.S. states, municipalities and political subdivisions [Member]
Investment Information
Fixed maturities credit impairment charges	0	1	14
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	$ 5	$ 2	$ 0

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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- Definition

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(9)(a))
-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(7)(c))
-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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