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Loans and Allowance for Loan and Lease Losses - Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
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Mar. 31, 2022 USD ($) | Mar. 31, 2022 Loan | Mar. 31, 2022 DebtSecurityNumber | Dec. 31, 2021 USD ($) | Dec. 31, 2021 Loan | Dec. 31, 2021 DebtSecurityNumber
Number of loans |  | 0 | 7 |  | 2 | 7
Pre- Modification Outstanding Principal Balance | $ 903 |  |  | $ 903 |  |
Post- Modification Principal Balance | 656 |  |  | 660 |  |
Real Estate [Member] | Construction, Land Development and Other Land Loans [Member] |  |  |  |  |  |
Number of loans | DebtSecurityNumber |  |  | 1 |  |  | 1
Pre- Modification Outstanding Principal Balance | 107 |  |  | 107 |  |
Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member] |  |  |  |  |  |
Number of loans | DebtSecurityNumber |  |  | 2 |  |  | 2
Pre- Modification Outstanding Principal Balance | 59 |  |  | 59 |  |
Post- Modification Principal Balance | 12 |  |  | 12 |  |
Real Estate [Member] | Secured By Non-farm Non residential Properties [Member] |  |  |  |  |  |
Number of loans | DebtSecurityNumber |  |  | 2 |  |  | 2
Pre- Modification Outstanding Principal Balance | 621 |  |  | 621 |  |
Post- Modification Principal Balance | 615 |  |  | 617 |  |
Commercial and Industrial Loans [Member] |  |  |  |  |  |
Number of loans | DebtSecurityNumber |  |  | 2 |  |  | 2
Pre- Modification Outstanding Principal Balance | 116 |  |  | 116 |  |
Post- Modification Principal Balance | $ 29 |  |  | $ 31 |  |

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- Definition Amount, after troubled debt restructuring, of modified financing receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524 + Details
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