Note 18 - Stock-based Compensation - Information Related to Stock Options (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Intrinsic value of options exercised	$ 89,080	$ 25,909
Exercise of stock options	149,228	55,314
Tax benefit from option exercises	24,866	21,240
Total weighted average fair value of options granted	$ 20,200	$ 653,859

The weighted average grant date value on stock options granted during the reporting period.

No definition available.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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