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Investments - Narrative (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Accrued Investment Income [Line Items] |  |
Accrued investment income | $ 77,110 | $ 76,892
5.90% Senior Notes |  |
Accrued Investment Income [Line Items] |  |
Interest rate (as a percent) | 5.90% |
Debt Securities, Available-For-Sale |  |
Accrued Investment Income [Line Items] |  |
Accrued investment income | $ 74,600 | $ 74,300

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