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Investment in Securities (Narrative) (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 USD ($) | Sep. 30, 2018 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2018 USD ($) | Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract] |  |  |  |  |
Number of securities that had an unrealized loss | 15 |  | 15 |  | 136
Number of securities that had an unrealized loss, greater than 12 months | 10 |  | 10 |  | 61
Percentage of total securities | 5.00% |  | 5.00% |  | 43.00%
Proceeds from sales of securities available-for-sale | $ 0 | $ 0 | $ 4,648 | $ 58,520 |
Gross realized gains |  |  | $ 19 | $ 42 |

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