Note 19 - Stock-based Compensation - Information Related to Stock Options (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Intrinsic value of options exercised	$ 42,616	$ 89,080
Exercise of stock options	70,035	149,228
Tax benefit from option exercises	10,708	24,866
Total weighted average fair value of options granted	$ 10,230	$ 20,200

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

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Amount of cash inflow from exercise of option under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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