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Securities (Details Textual) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 USD ($) Securities | Sep. 30, 2016 USD ($) | Sep. 30, 2017 USD ($) Securities | Sep. 30, 2016 USD ($) | Dec. 31, 2016 USD ($)
Schedule Of Available For Sale Securities [Line Items] |  |  |  |  |
Proceeds from sales of securities available for sale | $ 0 | $ 2,300,000 | $ 54,493,000 | $ 11,480,000 |
Gross gains realized | 0 | 31,000 | 730,000 | 224,000 |
Gross Losses realized | 0 | $ 0 | 731,000 | $ 152,000 |
Unrealized losses | $ 1,696,000 |  | $ 1,696,000 |  | $ 1,666,000
Number of securities | Securities | 541 |  | 541 |  |
Number of securities on unrealized loss position | Securities | 137 |  | 137 |  |
U.S. Treasury and U.S. government sponsored entities |  |  |  |  |
Schedule Of Available For Sale Securities [Line Items] |  |  |  |  |
Unrealized losses | $ 13,000 |  | $ 13,000 |  | $ 0
U.S. Treasury and U.S. government sponsored entities | Maximum |  |  |  |  |
Schedule Of Available For Sale Securities [Line Items] |  |  |  |  |
Unrealized losses | $ 1,000 |  | $ 1,000 |  |

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