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Securities (Narrative) (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 USD ($) security | Sep. 30, 2017 USD ($) | Sep. 30, 2018 USD ($) security | Sep. 30, 2017 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Proceeds from Sale of Debt Securities, Available-for-sale | $ | $ 0 | $ 0 | $ 32,330 | $ 0
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 481 |  | 481 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 153 |  | 153 |
Municipal Bonds [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 458 |  | 458 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 92 |  | 92 |
U.S. Government and Government-Sponsored Enterprise Securities [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 54 |  | 54 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 14 |  | 14 |
US Government Securities [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Number Of Securities In Continuous Loss Position For Twelve Months or More | 1 |  | 1 |
Number Of Securities In Unrealized Loss Position | 1 |  | 1 |

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