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Investments - Summary of Amounts Included in Net Realized (Losses) Gains and Other-Than-Temporary Impairments (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2026 | Mar. 31, 2025 | Dec. 31, 2025
Investment [Line Items] |  |  |
Foreign exchange (losses) gains | $ 1,189 | $ (1,582) |
Debt Securities, Available-for-sale, Allowance for Credit Loss, Not to Sell before Recovery, Credit Loss, Previously Recorded, Expense (Reversal) | 0 | 0 |
Realized Investment Gains (Losses) | 3 | (3) |
Fair Value of Securities Deposited in Connection wtih Letter of Credit | 152 |  | $ 153
Debt Securities, Available-for-sale, Realized Gain | 5 | 0 |
Debt Securities, Available-for-sale, Realized Loss | 2 | 3 |
Available-for-sale Securities, Gross Realized Losses | $ (2) | $ (3) |

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