Insurance Subsidiary Financial Information and Regulatory Matters - Narrative (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Statutory Accounting Practices [Line Items]
Decrease in statutory capital and surplus	$ 202		$ (152)
Increase to statutory capital for investment carried at net asset value	15	$ 13
Vermont \| Raven Reinsurance Company
Statutory Accounting Practices [Line Items]
Change in statutory capital surplus increase (decrease)	200		200
Statutory capital and surplus	$ 107		$ 121

Statutory Accounting Practices, Permitted Practice, Change in Statutory Capital and Surplus

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- Definition

Statutory Accounting Practices, Statutory Capital and Surplus, Increase (Decrease), Due To Investment Carried At Net Asset Values

+ References

No definition available.

+ Details

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- Definition

Statutory Accounting Practices, Statutory Capital and Surplus, Increase (Decrease) as a Result of ReDomestication by Entity

+ References

No definition available.

+ Details

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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 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

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- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

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-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479989/944-505-50-1

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