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v3.25.3

Investments - Additional Information (Details) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2025 USD ($) security | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Investments |  |  |
Accrued investment income | $ | $ 29,584 |  | $ 28,319
Number of debt securities for which there is an allowance for credit losses | security | 12 |  |
Number of debt securities in an unrealized loss position for which an allowance for credit losses has not been recorded | security | 1,077 |  |
Unrealized loss | $ | $ 150,368 |  | 224,611
Unrealized losses as percentage of fixed income portfolio cost basis | 4.00% |  |
Unrealized losses relative to total invested assets (as a percent) | 3.00% |  |
Number of unrealized loss positions | security | 1,077 |  |
Number of securities in unrealized loss positions for 12 months or longer | security | 926 |  |
Maximum |  |  |
Investments |  |  |
Losses on fixed income securities | $ | $ 1,000 | $ 0 |
Fixed Income Securities |  |  |
Investments |  |  |
Accrued investment income | $ | $ 28,000 |  | $ 27,000

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