Investments (Modifications to Borrowers Experiencing Financial Difficulty) (Details) - Commercial Mortgage Loans - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modified, Weighted Average Term Increase	Less than one year	Less than one year	Less than one year	Less than one year
Financing Receivable, Modified in Period, to Total Financing Receivables, Percentage	1.00%	1.00%	1.00%	1.00%
Extended Maturity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 39	$ 145	$ 236	$ 367

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

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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.

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