Investments (Amortized Cost Basis of Loan Modifications made to Borrowers Experiencing Financial Difficulties) (Details) - Commercial Portfolio Segment - Term Extension - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Financing Receivable, Modified [Line Items]
Financing Receivable, Modified in Period, Amount	$ 0	$ 8,078	$ 0	$ 14,546
Financing Receivable, Modified in Period, to Total Financing Receivables, Percentage	0.00%	0.10%	0.00%	0.20%

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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