Investments (Loan Valuation Allowance for Mortgage Loans) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Allowance For Loan And Lease Losses Roll Forward
Balance, Beginning of Period	$ 117	$ 93
Allowance For Loan And Lease Losses Writeoff Net Of Recoveries	7	0
Allowance For Loan and Lease Losses Provision Of Credit Losses	5	(4)
Real Estate [Line Items]
Allowance for Loan and Lease Losses, Real Estate	115	89
Allowance For Loan and Lease Losses Provision Of Credit Losses	(5)	4
Allowance For Loan And Lease Losses Writeoff Net Of Recoveries	(7)	0
Commercial Real Estate
Allowance For Loan And Lease Losses Roll Forward
Balance, Beginning of Period	112	93
Allowance For Loan And Lease Losses Writeoff Net Of Recoveries	7	0
Allowance For Loan and Lease Losses Provision Of Credit Losses	4	(6)
Real Estate [Line Items]
Allowance for Loan and Lease Losses, Real Estate	109	87
Allowance For Loan and Lease Losses Provision Of Credit Losses	(4)	6
Allowance For Loan And Lease Losses Writeoff Net Of Recoveries	(7)	0
Residential Real Estate
Allowance For Loan And Lease Losses Roll Forward
Balance, Beginning of Period	5	0
Allowance For Loan And Lease Losses Writeoff Net Of Recoveries	0	0
Allowance For Loan and Lease Losses Provision Of Credit Losses	1	2
Real Estate [Line Items]
Allowance for Loan and Lease Losses, Real Estate	6	2
Allowance For Loan and Lease Losses Provision Of Credit Losses	(1)	(2)
Allowance For Loan And Lease Losses Writeoff Net Of Recoveries	$ 0	$ 0

Allowance For Loan and Lease Losses Provision Of Credit Losses

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- Definition

Allowance For Loan And Lease Losses Writeoff Net Of Recoveries

+ References

No definition available.

+ Details

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- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ 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)(1)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ 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/2003/role/disclosureRef
-Topic 976
-SubTopic 310
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477332/976-310-50-1

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