Stock options and warrants (Other common stock purchase options and warrants) (Narrative) (Details) - Stock Issuance [Domain] - USD ($) |
6 Months Ended | ||
|---|---|---|---|
Jun. 30, 2015 |
Jun. 30, 2014 |
Dec. 31, 2014 |
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| Stock options and warrants [Abstract] | |||
| Shares issued for warrants exercised | 0 | 1,161,570 | |
| Value of shares issued for warrants exercised | $ 1,580,000 | ||
| Exercise price of warrants | $ 1.36 | ||
| Nonqualified [Member] | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Awards outstanding | 3,455,935 | 3,455,935 | |
| Options granted | |||
| Fair value of options vested | $ 0 | $ 0 | |
| Unrecognized compensation expense | $ 0 | ||
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- Definition Exercise price per share or per unit of warrants or rights outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Unrecognized cost of unvested share-based compensation awards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. 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 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 Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares issued during the period as a result of the conversion of convertible securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The gross value of stock issued during the period upon the conversion of convertible securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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