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Loans and Allowance for Loan and Lease Losses - Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Impaired loans with no related allowance recorded, carrying amount | $ 5,608 | $ 7,009 |
Impaired loans with no related allowance recorded, unpaid principal balance | 5,608 | 7,009 |
Impaired loans, related allowances | 72 | 74 | $ 74
Impaired loans with an allowance recorded, carrying amount | 100 | 102 |
Impaired loans with an allowance recorded, unpaid principal balance | 100 | 102 |
Impaired loans, carrying amount | 5,708 | 7,111 |
Impaired loans, unpaid principal balance | 5,708 |  | 7,111
Impaired loans, average recorded investment | 5,681 | 3,533 |
Impaired loans, interest income recognized | 126 | 46 |
Impaired loans, interest income received | 92 | 47 |
Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member] |  |  |
Impaired loans with no related allowance recorded, carrying amount | 863 | 885 |
Impaired loans with no related allowance recorded, unpaid principal balance | 863 | 885 |
Impaired loans, related allowances | 11 | 12 | 12
Impaired loans with an allowance recorded, carrying amount | 18 | 18 |
Impaired loans with an allowance recorded, unpaid principal balance | 18 | 18 |
Impaired loans, carrying amount | 881 | 903 |
Impaired loans, unpaid principal balance | 881 |  | 903
Impaired loans, average recorded investment | 911 | 923 |
Impaired loans, interest income recognized | 2 | 10 |
Impaired loans, interest income received | 2 | 10 |
Real Estate [Member] | Secured By Non-farm Non residential Properties [Member] |  |  |
Impaired loans with no related allowance recorded, carrying amount | 4,237 | 5,594 |
Impaired loans with no related allowance recorded, unpaid principal balance | 4,237 | 5,594 |
Impaired loans, carrying amount | 4,237 | 5,594 |
Impaired loans, unpaid principal balance | 4,237 |  | 5,594
Impaired loans, average recorded investment | 4,270 | 2,467 |
Impaired loans, interest income recognized | 101 | 28 |
Impaired loans, interest income received | 68 | 28 |
Commercial and Industrial Loans [Member] |  |  |
Impaired loans with no related allowance recorded, carrying amount | 508 | 530 |
Impaired loans with no related allowance recorded, unpaid principal balance | 508 | 530 |
Impaired loans, related allowances | 60 | 61 | 61
Impaired loans with an allowance recorded, carrying amount | 59 | 60 |
Impaired loans with an allowance recorded, unpaid principal balance | 59 | 60 |
Impaired loans, carrying amount | 567 | 590 |
Impaired loans, unpaid principal balance | 567 |  | 590
Impaired loans, average recorded investment | 477 | 118 |
Impaired loans, interest income recognized | 22 | 7 |
Impaired loans, interest income received | 21 | 7 |
Direct Consumer [Member] |  |  |
Impaired loans, related allowances | 1 | 1 | 1
Impaired loans with an allowance recorded, carrying amount | 23 | 24 |
Impaired loans with an allowance recorded, unpaid principal balance | 23 | 24 |
Impaired loans, carrying amount | 23 | 24 |
Impaired loans, unpaid principal balance | 23 |  | $ 24
Impaired loans, average recorded investment | 23 | 25 |
Impaired loans, interest income recognized | 1 | 1 |
Impaired loans, interest income received | $ 1 | $ 2 |

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