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Fair Value of Financial Instruments (Company's Assets And Liabilities Measured At Fair Value On Recurring Basis) (Parenthetical) (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Exchange-traded bond fund	$ 10	$ 10
Corporate Obligations [Member] | Loans Carried at Fair Value [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable at fair value	$ 16	$ 15

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- Definition

Exchange-traded bond fund.

+ References

No definition available.

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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 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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