Stock-based compensation - Narrative (Details) - USD ($) |
1 Months Ended | 3 Months Ended | ||
|---|---|---|---|---|
Oct. 31, 2013 |
Mar. 31, 2016 |
Mar. 31, 2015 |
Dec. 31, 2015 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Options outstanding (in shares) | 1,407,512 | 1,672,578 | ||
| Stock-based compensation | $ 143,967 | $ 178,000 | ||
| Stock Options | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Unrecognized compensation cost related to unvested stock-based awards | $ 1,500,000 | |||
| Unrecognized compensation cost, recognition period | 3 years | |||
| Options granted, weighted-average grant date fair value | $ 1.86 | |||
| Stock Options | General and Administrative Expense | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Stock-based compensation | $ 143,967 | $ 178,000 | ||
| The 2013 Plan | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Authorized shares | 4,773,992 | |||
| Contractual term | 10 years | |||
| Award vesting period | 5 years | |||
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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 Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. 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 The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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- 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 Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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