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Troubled Debt Restructurings (Details Textual) $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($) Investment | Dec. 31, 2016 USD ($) Investment
Troubled Debt Restructurings (Textual) |  |
Total number of loans classified under troubled debt restructurings (TDRs) | 21 | 17
Total sum of loans classified as troubled debt restructurings (TDRs) | $ | $ 7.8 | $ 6.7
Number of months previous loan payment defaulted | 12 months | 12 months
Commercial [Member] |  |
Troubled Debt Restructurings (Textual) |  |
Total number of loans added under troubled debt restructurings (TDRs) | 5 |
Total sum of loans added as troubled debt restructurings (TDRs) | $ | $ 2.6 |
Total number of loans removed under TDR | 4 |
Total number of nonaccrual loans restored | 4 |
Consumer [Member] |  |
Troubled Debt Restructurings (Textual) |  |
Total number of loans added under troubled debt restructurings (TDRs) | 3 |
Total sum of loans added as troubled debt restructurings (TDRs) | $ | $ 2.6 |
Total number of loans removed under TDR | 4 |
Total number of nonaccrual loans restored | 4 |

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