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Investments - Summary of Net Investment Income (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Investment [Line Items] |  |  |  |
Interest Income, Debt Securities, Available-for-Sale, Operating | $ 2,609 | $ 4,149 | $ 5,503 | $ 7,818
Short-term Investments [Member] |  |  |  |
Investment [Line Items] |  |  |  |
Gross Investment Income, Operating | 1,191 | 2,988 | 2,648 | 5,577
Fixed Income Investments [Member] |  |  |  |
Investment [Line Items] |  |  |  |
Gross Investment Income, Operating | 1,470 | 1,263 | 2,870 | 2,434
Fixed Income Securities, Trading |  |  |  |
Investment [Line Items] |  |  |  |
Gross Investment Income, Operating | 0 | (386) | (79) | (415)
Principal Amount Outstanding of Loans Held-in-portfolio |  |  |  |
Investment [Line Items] |  |  |  |
Gross Investment Income, Operating | $ 35 | $ 0 | $ 69 | $ 0

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