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Investment Securities - Narrative (Details) | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2019 USD ($) security | Dec. 31, 2020 USD ($) loan state security | Dec. 31, 2019 USD ($) security | Dec. 31, 2018 USD ($) | Sep. 30, 2014 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Number of securities temporarily impaired (security) | security | 86 | 50 | 86 |  |
Number of securities temporarily impaired for 12 months or more (security) | security | 28 | 10 | 28 |  |
Period of temporary impairment |  | 12 months | 12 months |  |
Amortized cost of securities transferred |  | $ 24,900,000 |  |  | $ 89,780,000
Net unrealized gains (losses) on securities transferred |  | 1,600,000 |  |  | (15,000)
Proceeds from sales of securities available for sale | $ 4,300,000 | 103,579,000 | $ 8,339,000 | $ 459,000 |
Gain on sale of securities | 209,000 | 1,155,000 | 224,000 |  |
Fair value of securities transferred |  |  |  |  | $ 89,757,000
Net unrealized loss on securities transferred from available for sale to held to maturity | (182,000) | $ (133,000) | (182,000) |  |
Number of states | state |  | 6 |  |  |
Federal Home Loan Bank Stock | 7,945,000 | $ 9,508,000 | 7,945,000 |  |
Impairment losses |  | $ 0 |  |  |
State and political subdivisions |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Number of securities temporarily impaired (security) | loan |  | 28 |  |  |
Proceeds from sale of held-to-maturity securities |  | $ 8,600,000 |  |  |
Cumulative book value |  | 8,313,000 |  |  |
Net realized gain from sale of municipal securities |  | 268,000 |  |  |
Other equity securities |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Securities pledged as collateral | $ 214,173,000 | $ 297,326,000 | $ 214,173,000 |  |

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