Note 11 - Share-based Compensation - Schedule of Share-based Compensation Expense Based on Fair Value of Options (Details) - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Expected lives at date of grant (in years) (Year)	4 years 229 days	3 years 302 days
Weighted average fair value of options granted (in dollars per share)	$ 1.61	$ 1
Minimum [Member]
Expected volatility	36.00%	35.00%
Risk free interest rate	1.80%	2.43%
Maximum [Member]
Expected volatility	38.00%	49.00%
Risk free interest rate	2.36%	2.88%

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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