Stock-based compensation (Details) - Employee Stock Option [Member] $ / shares in Units, $ in Thousands |
3 Months Ended |
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Mar. 31, 2016
USD ($)
$ / shares
shares
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| Number of shares available for grant | |
| Shares available for future grant, beginning balance | 29,485 |
| Number of shares, Granted | 0 |
| Number of shares, Cancelled | 0 |
| Shares available for future grant, ending balance | 29,485 |
| Option activity | |
| Number of shares, Outstanding beginning balance | 43,071 |
| Number of shares, Exercised | (20) |
| Number of shares, Granted | 0 |
| Number of shares, Cancelled | 0 |
| Number of shares, Outstanding ending balance | 43,051 |
| Weighted average exercise price, Outstanding beginning balance | $ / shares | $ 0.48 |
| Weighted average exercise price, Exercised | $ / shares | 0.15 |
| Weighted average exercise price, Outstanding ending balance | $ / shares | $ 0.48 |
| Aggregate intrinsic value, Outstanding beginning balance | $ | $ 9,252 |
| Aggregate intrinsic value, options exercised | $ | (11) |
| Aggregate intrinsic value, Outstanding ending balance | $ | $ 9,041 |
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- References No definition available.
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- References No definition available.
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- 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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- Definition Gross number of share options (or share units) granted during the period. No definition available.
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- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- 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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- 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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- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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