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

The amount of a reclassification adjustment made to current period financial statement amounts.

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- Definition

Discounted percentage to account for selling and marketing costs.

+ References

No definition available.

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- Definition

Percentage of loan portfolio concentrated in loans secured by real estate.

+ References

No definition available.

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- Definition

Minimum probability of uncertain tax positions of being realized upon settlement.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6812-107765

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