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Securities (Narrative) (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 USD ($) issuance security | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |
Number Of Issuances Of Securities Exceeding Shareholders Equity Threshold | issuance | 0 |  |
Proceeds from Sale of Debt Securities, Available-for-sale | $ | $ 259,554 | $ 32,330 | $ 30,403
US Government Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 0 |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 0 |  |
Other Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Issuances Of Securities Exceeding Shareholders Equity Threshold, Percent | 10.00% |  |
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 | 243 |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 162 |  |
Municipal Bonds [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 24 |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 14 |  |
US Government Corporations and Agencies Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 3 |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 3 |  |

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