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Loans and Allowance for Loan Losses - Narrative (Details) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2018 USD ($) loan segment | Dec. 31, 2017 USD ($) contract
Financing Receivable, Modifications [Line Items] |  |
Loan portfolio segments | segment | 5 |
Number of contracts | contract |  | 0
Foreclosed assets | $ 4,230,451 | $ 3,254,392
Trouble Debt Restructuring [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Loans that met criteria for restructured | $ 693,000 | $ 41,000
Number of contracts, nonaccrual | loan | 0 |
Residential Real Estate [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Foreclosed assets | $ 425,000 |
Commercial Real Estate [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Loans that met criteria for restructured | $ 622,000 |
Number of contracts | loan | 1 |
Consumer Real Estate [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Loans that met criteria for restructured | $ 34,000 |
Number of contracts | loan | 1 |

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