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Investments (Unrealized Gains (Losses) on Equity Securities) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2023 | Mar. 31, 2022
Gain (Loss) on Securities [Line Items] |  |
Unrealized gains (losses) recognized in income on equity securities remaining in our portfolio at period end. | $ (142) | $ (2,220)
Unrealized gains (losses) recognized in income on equity securities sold during period | 3,390 | 66
Total unrealized gains (losses) recognized in income on equity securities | $ 3,248 | $ (2,154)

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