Note 6 - Stock Option Plans (Details Textual) - USD ($) |
3 Months Ended | |
|---|---|---|
Mar. 31, 2017 |
Mar. 31, 2016 |
|
| Employee Stock Option [Member] | ||
| Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount | $ 133,810 | $ 134,405 |
| Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized | $ 734,114 | $ 1,026,024 |
| Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition | 2 years 255 days | 2 years 361 days |
| Non-employee Options [Member] | ||
| Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount | $ 17,092 | $ 1,175 |
| X | ||||||||||
- Definition Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Unrecognized cost of unvested share-based compensation awards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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