Note 20 - Fair Value of Financial Instruments and Fair Value Measurements - Fair Value Measurement Using Significant Unobservable Inputs (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Transfers out of Level 3	$ (2,009,080)
Available-for-sale Securities [Member]
Balance, available for sale securities	7,297,497	$ 576,384	$ 930,311
Transfers out of Level 3	(2,009,080)
Securities Purchased During the Year		7,069,649
Securities Matured During the Year		(360,000)	(330,000)
Paydowns on Securities	(885,082)
Comprehensive Income	(125,767)	11,464	(23,927)
Balance, available for sale securities	$ 4,277,568	$ 7,297,497	$ 576,384

Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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