Stock based compensation, options and warrants (Schedule of Recognized Stock-based Compensation) (Details) - USD ($) |
3 Months Ended | |
|---|---|---|
Mar. 31, 2019 |
Mar. 31, 2018 |
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| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||
| Total stock-based compensation | $ 235,042 | $ 883,943 |
| Restricted Stock [Member] | ||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||
| Total stock-based compensation | 176,544 | 766,949 |
| Stock options awards under the Plan Member [Member] | ||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||
| Total stock-based compensation | $ 58,498 | $ 116,994 |
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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