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Securities (Narrative) (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 USD ($) security | Sep. 30, 2018 USD ($) | Sep. 30, 2019 USD ($) security | Sep. 30, 2018 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Proceeds from Sale of Debt Securities, Available-for-sale | $ | $ 0 | $ 0 | $ 259,554 | $ 32,330
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 | 170 |  | 170 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 211 |  | 211 |
Asset-backed Securities [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 6 |  | 6 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 6 |  | 6 |
Municipal Bonds [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 27 |  | 27 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 81 |  | 81 |
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 | 7 |  | 7 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 7 |  | 7 |
US Government Securities [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 1 |  | 1 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 1 |  | 1 |

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