Note 7 - Stock Options Activity (Details) - $ / shares |
9 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2015 |
Dec. 31, 2014 |
|
| Outstanding at December 31, 2014 (in shares) | 314,775 | |
| Outstanding at December 31, 2014 (in dollars per share) | $ 2.23 | |
| Outstanding at December 31, 2014 (in dollars per share) | $ 2.21 | $ 0.92 |
| Outstanding at December 31, 2014 | 9 years | 9 years 73 days |
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | 211,660 | |
| Granted at market price (in dollars per share) | $ 8.35 | |
| Cancelled (in shares) | (1,835) | |
| Cancelled (in dollars per share) | $ 3.49 | |
| Outstanding at September 30, 2015 (in shares) | 524,600 | 314,775 |
| Outstanding at September 30, 2015 (in dollars per share) | $ 4.69 | $ 2.23 |
| Exercisable at September 30, 2015 (in shares) | 111,502 | |
| Exercisable at September 30, 2015 (in dollars per share) | $ 1.81 | |
| Exercisable at September 30, 2015 (in dollars per share) | $ 0.82 | |
| Exercisable at September 30, 2015 | 8 years 146 days |
| X | ||||||||||
- Definition The weighted-average fair value as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. No definition available.
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| X | ||||||||||
- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Weighted average price of options that were either forfeited or expired. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Gross number of share options (or share units) granted during the period. No definition available.
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| X | ||||||||||
- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
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| X | ||||||||||
- Definition Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, 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 | ||||||||||
- Definition Weighted average remaining contractual term for option awards outstanding, 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 | ||||||||||
- Definition Weighted average grant-date fair value of options vested. No definition available.
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