Note 10 - Share-based Compensation - Schedule of Share-based Compensation Expense Based on Fair Value of Options (Details) - $ / shares |
12 Months Ended | |
|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Expected volatility | 35.00% | |
| Risk free interest rate | 0.69% | |
| Expected lives at date of grant (Year) | 3 years 339 days | 5 years 3 days |
| Weighted average fair value of options granted (in dollars per share) | $ 2.09 | $ 2.76 |
| Minimum [Member] | ||
| Expected volatility | 30.00% | |
| Risk free interest rate | 0.69% | |
| Maximum [Member] | ||
| Expected volatility | 69.00% | |
| Risk free interest rate | 2.05% | |
| X | ||||||||||
- Definition Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award. No definition available.
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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