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

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

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- Definition

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

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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://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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