Investments (Amortized Cost Basis of Loan Modifications made to Borrowers Experiencing Financial Difficulties) (Details) - Commercial mortgage loans - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Term Extension
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 0	$ 0	$ 0	$ 14,546
Amortized cost, percent	0.00%	0.10%	0.00%	0.30%
Other Than Insignificant Delay in Payment
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 0	$ 4,570	$ 0	$ 4,570

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.

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