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Loans (Details Textual) | 12 Months Ended
--- | ---
Dec. 31, 2017 USD ($) Loans | Dec. 31, 2016 USD ($) Loans | Dec. 31, 2015 USD ($) Loans
Financing Receivable Modifications [Line Items] |  |  |
Total troubled debt restructurings | $ 5,000,000 | $ 7,000,000 |
Specific reserves to customers | 162,000 | 249,000 |
Commitments to lend additional amounts to borrowers classified as troubled debt restructurings | 0 | 0 |
Allowance adjustment charge offs | 75,000 | 344,000 | $ 129,000
Increase in the allowance for loan losses as a result of the allowance | $ 75,000 | 43,000 | 101,000
Troubled debt restructured loans with subsequent payment defaults | Loans | Loans | 0 |  |
Loans default payment past due period | 30 days |  |
Maximum commercial loan and commercial real estate relationships | $ 750,000 |  |
Commercial real estate loan |  |  |
Financing Receivable Modifications [Line Items] |  |  |
Total troubled debt restructurings |  | $ 1,200,000 | $ 40,000
Troubled debt restructured loans with subsequent payment defaults | Loans | Loans |  | 2 | 1
Residential real estate loan |  |  |
Financing Receivable Modifications [Line Items] |  |  |
Total troubled debt restructurings |  | $ 1,000 | $ 1,000
Troubled debt restructured loans with subsequent payment defaults | Loans | Loans |  | 1 | 1
Residential real estate, Home equity lines of credit |  |  |
Financing Receivable Modifications [Line Items] |  |  |
Total troubled debt restructurings |  | $ 10,000 | $ 11,000
Troubled debt restructured loans with subsequent payment defaults | Loans | Loans |  | 1 | 1
Troubled debt restructurings |  |  |
Financing Receivable Modifications [Line Items] |  |  |
Specific reserves to customers | $ 68,000 | $ 101,000 |
Contractual Interest Rate Reduction | Minimum |  |  |
Financing Receivable Modifications [Line Items] |  |  |
Reduction of the notes stated interest rate | 0.49% |  |
Contractual Interest Rate Reduction | Maximum |  |  |
Financing Receivable Modifications [Line Items] |  |  |
Reduction of the notes stated interest rate | 11.51% |  |
Extended Maturity | Minimum |  |  |
Financing Receivable Modifications [Line Items] |  |  |
Maturity period loans | 6 months |  |
Extended Maturity | Maximum |  |  |
Financing Receivable Modifications [Line Items] |  |  |
Maturity period loans | 132 months |  |

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