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Securities (Narrative) (Details) | Sep. 30, 2021 USD ($) investment | Dec. 31, 2020 USD ($) 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 | $ 190,514,000 | $ 237,506,000 |
Allowance for Credit Losses | 0 | 0 |
Accrued interest receivable on available-for-sale debt securities | 8,143,000 | 5,954,000 |
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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