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v3.20.1

Securities (Narrative) (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 USD ($) security | Mar. 31, 2019 USD ($) | Dec. 31, 2019 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |
Interest receivable | $ | $ 44,577 |  | $ 46,839
Proceeds from Sale of Debt Securities, Available-for-sale | $ | $ 194,105 | $ 83,968 |
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 | 64 |  |
Available-for-sale Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Interest receivable | $ | $ 12,300 |  | $ 13,900
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 | 0 |  |
Asset-backed Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 5 |  |
State and Municipal Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 41 |  |

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