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Investments (Investments in Marketable Equity Securities) (Details 1) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
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Investments [Abstract] |  |
Total Cost | $ 231,976 | $ 227,153
Gross unrealized gains | 663,867 | 627,760
Gross unrealized losses | (6,328) | (2,479)
Investments in Marketable Equity Securities | $ 889,515 | $ 852,434

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