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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, 2018
Percentage of Loan Portfolio Concentrated in Loans Secured by Real Estate. |  | 88.00%
Discounted Percentage to Account for Selling and Marketing Costs |  | 10.00%
Open Tax Year |  | 2018 2017 2016 2015
Probability of Uncertain Tax Positions of Being Realized upon Settlement, Minimum |  | 50.00%
Cash Surrender Value of Life Insurance | $ 17,088,693 | $ 17,597,639
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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