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Investments (Unrealized Gains (Losses) on Equity Securities) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Gain (Loss) on Securities [Line Items] |  |
Unrealized gains (losses) recognized in income on equity securities on securities remaining in our portfolio at period end. | $ (2,220) | $ 10,097
Unrealized (losses) gains recognized in income on equity securities on securities sold during period | 66 | 1,183
Total unrealized (losses) gains recognized in income on equity securities | (2,154) | $ 11,280
Change in Gain (Loss) on Investments | $ (45,500) |

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