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Loans - Narrative (Details) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) loan | Sep. 30, 2020 USD ($) loan
Loans and Leases Receivable Disclosure [Line Items] |  |  |  |
Outstanding balance of high risk loans, minimum | $ 250,000 |  | $ 250,000 |
Interest income on impaired loans | 261,000 | $ 104,000 | 825,000 | $ 154,000
Unfunded commitments to lend | 0 |  | $ 0 |
Number of loans that subsequently defaulted | loan |  |  | 0 | 0
Construction, land and land development |  |  |  |
Loans and Leases Receivable Disclosure [Line Items] |  |  |  |
Loan contracts restructured | loan |  |  | 1 |
Troubled debt restructuring | $ 511,000 |  | $ 511,000 |

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