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Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016
Percentage of Loan Portfolio Concentrated in Loans Secured by Real Estate. |  | 87.10% |
Discounted Percentage to Account for Selling and Marketing Costs | 10.00% | 10.00% |
Probability of Uncertain Tax Positions of Being Realized upon Settlement, Minimum | 50.00% | 50.00% |
Cash Surrender Value of Life Insurance | $ 17,088,693 | $ 17,088,693 | $ 15,419,269
Reclassification from AOCI to Retained Earnings Due to Stranded Tax Effects from the TCJ Act [Member] |  |  |
Current Period Reclassification Adjustment | $ 1,068,295 |  |

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