Fair Value Measurements - Fair Value of Life Policy Loans, Deferred Annuities, and Structured Settlements (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of life policy loans	$ 37	$ 37
Liabilities Related to Investment Contracts, Fair Value Disclosure	752	764
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of life policy loans	0	0
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of life policy loans	0	0
Liabilities Related to Investment Contracts, Fair Value Disclosure	144	143
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of life policy loans	37	37
Liabilities Related to Investment Contracts, Fair Value Disclosure	608	621
Deferred annuities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	608	621
Deferred annuities \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Deferred annuities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Deferred annuities \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	608	621
Structured settlements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	144	143
Structured settlements \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	0	0
Structured settlements \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	144	143
Structured settlements \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities Related to Investment Contracts, Fair Value Disclosure	$ 0	$ 0

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-3

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Fair value portion of liability related to investment contracts for example, but not limited to, guaranteed investment contract or annuities.

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-Name Accounting Standards Codification
-Topic 944
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-Publisher FASB
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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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-Name Accounting Standards Codification
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