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Investments (Unrealized Gains (Losses) on Equity Securities) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Gain (Loss) on Securities [Line Items] |  |  |  |
Unrealized gains (losses) recognized in income on equity securities on securities remaining in our portfolio at September 30, 2020 | $ 4,338 | $ 1,109 | $ (7,101) | $ 1,805
Unrealized gains (losses) recognized in income on equity securities on securities sold in each respective period | 0 | (21,426) | 3 | (9,896)
Total unrealized gains (losses) recognized in income on equity securities | $ 4,338 | $ (20,317) | $ (7,098) | $ (8,091)

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