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Loans and Allowance for Loan Losses - Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands | 9 Months Ended | 12 Months Ended
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Sep. 30, 2019 USD ($) DebtSecurityNumber | Dec. 31, 2018 USD ($) DebtSecurityNumber
Number of Loans | DebtSecurityNumber | 6 | 7
Pre- Modification Outstanding Principal Balance | $ 541 | $ 594
Post- Modification Principal Balance | $ 159 | $ 297
Real Estate [Member] | Construction, Land Development and Other Land Loans [Member] |  |
Number of Loans | DebtSecurityNumber | 1 | 1
Pre- Modification Outstanding Principal Balance | $ 107 | $ 107
Post- Modification Principal Balance | $ 66 | $ 73
Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member] |  |
Number of Loans | DebtSecurityNumber | 3 | 3
Pre- Modification Outstanding Principal Balance | $ 318 | $ 318
Post- Modification Principal Balance | $ 30 | $ 118
Real Estate [Member] | Secured By Non-farm Non residential Properties [Member] |  |
Number of Loans | DebtSecurityNumber |  | 1
Pre- Modification Outstanding Principal Balance |  | $ 53
Post- Modification Principal Balance |  | $ 34
Commercial and Industrial Loans [Member] |  |
Number of Loans | DebtSecurityNumber | 2 | 2
Pre- Modification Outstanding Principal Balance | $ 116 | $ 116
Post- Modification Principal Balance | $ 63 | $ 72

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