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Investment Securities - Realized Gains and Losses From Sale of Securities (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Realized Investment Gains (Losses) [Abstract] |  |  |  |
Gross gains | $ 116 | $ 51 | $ 934 | $ 365
Gross losses | $ (21) | $ 0 | $ (21) | $ (42)

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- Definition Debt and equity securities available for sale realized loss. + References No definition available. + Details
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