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Investment Securities - Summary of Interest Income on Available-For-Sale Investment Securities (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Total taxable interest income | $ 917 | $ 1,516 | $ 3,879 | $ 4,756
Total tax-exempt interest income | 23 | 12 | 72 | 94
Total interest income | 940 | 1,528 | 3,951 | 4,850
U.S. Treasury and government sponsored entities |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Total taxable interest income | 680 | 943 | 2,839 | 3,085
Other |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Total taxable interest income | 237 | 573 | 1,040 | 1,671
Municipal securities |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Total tax-exempt interest income | $ 23 | $ 12 | $ 72 | $ 94

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