Stockholders' equity (Details) - shares |
Mar. 31, 2016 |
Dec. 31, 2015 |
Mar. 31, 2015 |
Dec. 31, 2014 |
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| Stockholders Equity Details | ||||
| Stock options issued and outstanding | 43,051 | |||
| Authorized for future option grants | 29,485 | |||
| Warrants outstanding | 6,175 | 8,280 | 12,680 | 26,669 |
| Total | 78,711 |
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- References No definition available.
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- References No definition available.
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- Definition Number of warrants or rights outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of common shares reserved for future issuance related to deferred compensation arrangements with individuals. No definition available.
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- Definition The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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