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LOANS - Summary of Impaired Loans, Excluding Purchased Impaired (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Impaired loans |  |  |  |  |
Loans with allowance allocation | $ 21,688 |  | $ 21,688 |  | $ 27,437
Loans without allowance allocation | 9,145 |  | 9,145 |  | 8,138
Carrying balance | 30,833 |  | 30,833 |  | 35,575
Contractual balance | 33,357 |  | 33,357 |  | 38,362
Specifically allocated allowance | 1,834 |  | 1,834 |  | $ 3,874
Average carrying balance of individually assessed loans | 31,500 | $ 8,800 | 34,100 | $ 4,200 |
Interest income on individually assessed loans | $ 0 | $ 0 | $ 0 | $ 0 |

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