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Investment in Securities (Narrative) (Details) $ in Thousands | 3 Months Ended
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Mar. 31, 2021 USD ($) | Mar. 31, 2020 USD ($)
Investments, Debt and Equity Securities [Abstract] |  |
Number of securities that had an unrealized loss | 33 |
Number of securities that had an unrealized loss, greater than 12 months | 0 |
Percentage of total securities | 12.00% |
Proceeds from sales of securities available-for-sale | $ 2,991 | $ 19,629
Gross realized gains | $ 48 | $ 1,069

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