Investments (Modifications to Borrowers Experiencing Financial Difficulty) (Details) - Commercial Mortgage Loans - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modified, Weighted Average Term Increase	5	Less than one year	5	Less than one year
Financing Receivable, Modified in Period, to Total Financing Receivables, Percentage	1.00%	1.00%	1.10%	1.00%
Extended Maturity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 339	$ 156	$ 589	$ 236

Financing Receivable, Modified, Weighted Average Term Increase

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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
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Publisher FASB
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- Definition

Percentage of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

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- Definition

Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

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-Paragraph 42
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