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Securities (Additional Information) (Details) | Sep. 30, 2020 USD ($) investment | Dec. 31, 2019 USD ($) investment | Dec. 31, 2009 USD ($)
--- | --- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |  |
Carrying value of securities pledged to secure repurchase agreements, public and trust deposits and other by law | $ 224,379,000 | $ 245,664,000 |
Allowance for Credit Losses | 0 |  |
Accrued interest receivable on debt securities available-for-sale | 5,255,000 |  |
Original amount in non-controlling investment security in a single banking organization | 353,000 | $ 353,000 | $ 1,350,000
Additional impairment on equity securities recognized through earnings | $ 0 |  | $ 997,000
Equity Securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Number of non-controlling investments in a single banking organization | investment | 1 | 1 |

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