Note 13 - Federal and State Income Taxes - Unrecognized Tax Benefits (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Balance, beginning	$ 1,293,268	$ 1,346,967
Impact of tax positions taken during current year	286,994	333,253
Gross decrease related to tax positions of prior years	(178,058)	(40,584)
Reduction as a result of a lapse of the applicable statute of limitations	(153,565)	(346,368)
Balance, ending	$ 1,248,639	$ 1,293,268

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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