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Securities (Narrative) (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 USD ($) investment | Dec. 31, 2009 USD ($) | Dec. 31, 2017 USD ($) investment
Investments, Debt and Equity Securities [Abstract] |  |  |
Carrying amount of securities pledged | $ 211,239,000 |  | $ 165,404,000
Debt Securities, Available-for-sale [Line Items] |  |  |
Original investment of equity security | 353,000 |  | $ 353,000
Charge recognized through earnings due to decline in fair value of equity security | $ 0 |  |
Equity Securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Number of equity securities held in non-controlling investment banking | investment | 1 |  | 1
Original investment of equity security |  | $ 1,350,000 |
Other than temporary impairment losses in available for sale securities recognized |  | $ 997,000 |

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