Stock options and warrants (Schedule of Nonvested Awards) (Details) - Stock Incentive Plan [Member] - $ / shares |
6 Months Ended | |
|---|---|---|
Jun. 30, 2016 |
Jun. 30, 2015 |
|
| Nonvested Shares Underlying Options | ||
| Beginning balance | 33,336 | |
| Granted | 227,000 | |
| Vested | (54,028) | |
| Forfeited | (3,620) | (20,614) |
| Ending balance | 202,688 | |
| Weighted Average Exercise Price | ||
| Beginning balance | $ 15.54 | |
| Granted | 2.89 | |
| Vested | 6.67 | |
| Forfeited | 15.13 | $ 16.48 |
| Ending balance | 3.75 | |
| Weighted Average Grant Date Fair Value | ||
| Beginning balance | 11.41 | |
| Granted | 2.13 | |
| Vested | 5.02 | |
| Forfeited | 10.75 | |
| Ending balance | $ 2.73 | |
| X | ||||||||||
- Definition Weighted average exercise price of share-based payment awards that vested during the period. No definition available.
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- Definition Weighted average exercise price of nonvested options outstanding. No definition available.
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- Definition Gross number of share options (or share units) granted during the period. No definition available.
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- 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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- 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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- Definition Number of non-vested options outstanding. No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Number of non-vested options forfeited. No definition available.
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- Definition Weighted average grant-date fair value of non-vested options forfeited. No definition available.
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- Definition Weighted average grant-date fair value of non-vested options outstanding. No definition available.
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- References No definition available.
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- Definition Number of options vested. No definition available.
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- Definition Weighted average grant-date fair value of options vested. No definition available.
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- Details
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