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Disclosures about Fair Value of Assets and Liabilities (Details Textual) | 12 Months Ended
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Dec. 31, 2018
Disclosures About Fair Value of Assets and Liabilities (Textual) |
Interest rate on mortgage service, description | The mortgage servicing rights have increased in value. The servicing rights have had a decline in prepayments and the 0.49 percent decrease in the constant prepayment rate reflects the change in market rates.

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