Fair value measurements (Schedule of Changes in Level 3 Liabilities Measured at Fair Value) (Details) - Fair Value, Inputs, Level 3 [Member] |
3 Months Ended |
|---|---|
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Mar. 31, 2019
USD ($)
| |
| Convertible Notes [Member] | |
| Issuance of senior secured convertible notes | $ 6,330,726 |
| Issuance of warrants in connection with convertible notes | |
| Balance at January 28, 2019 | 6,330,726 |
| Change in fair value | 1,644,582 |
| Balance at March 31, 2019 | 7,975,308 |
| Warrant Liability [Member] | |
| Issuance of senior secured convertible notes | |
| Issuance of warrants in connection with convertible notes | 2,568,934 |
| Balance at January 28, 2019 | 2,568,934 |
| Change in fair value | 2,753,228 |
| Balance at March 31, 2019 | $ 5,322,162 |
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- Definition Change in fair value. No definition available.
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- Definition Fair value of financial and nonfinancial obligations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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