Note 13 - Share-based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands |
6 Months Ended | ||
|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Dec. 31, 2018 |
|
| Exercised (in shares) | (16,954) | ||
| Share-based Payment Arrangement, Option [Member] | |||
| Balance (in shares) | 639,359 | ||
| Granted (in shares) | 670,825 | ||
| Exercised (in shares) | (50,000) | ||
| Expired/cancelled (in shares) | (7,186) | ||
| Forfeited (in shares) | (3,439) | ||
| Balance (in shares) | 1,249,559 | ||
| Balance, weighted average exercise price (in dollars per share) | $ 5.90 | ||
| Granted, weighted average exercise price (in dollars per share) | 4.56 | ||
| Exercised, weighted average exercise price (in dollars per share) | 1.50 | ||
| Expired / cancelled, weighted average exercise price (in dollars per share) | 5.37 | ||
| Forfeited, weighted average exercise price (in dollars per share) | 6.65 | ||
| Balances, weighted average exercise price (in dollars per share) | $ 5.41 | ||
| Balance, aggregate intrinsic value | $ 460 | ||
| X | ||||||||||
- Definition Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Gross number of share options (or share units) granted during the period. No definition available.
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| X | ||||||||||
- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
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| X | ||||||||||
- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired. No definition available.
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| X | ||||||||||
- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated. No definition available.
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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 Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Details
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