Fair value of financial instruments (Details Textual) - USD ($) |
3 Months Ended | 6 Months Ended | 12 Months Ended |
|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2019 |
Dec. 31, 2018 |
|
| Assets, Fair Value Disclosure | $ 215,000 | $ 215,000 | |
| Unrealized Gain Loss on Investments in warrants | 55,000 | ||
| Proceeds from Issuance of Warrants | 215,000 | $ 67,000 | |
| Warrant [Member] | |||
| Proceeds from Issuance of Warrants | $ 152,000 | $ 0 |
| X | ||||||||||
- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- 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
|
| X | ||||||||||
- Definition Represents gain arises from fair value change on investments in warrants. No definition available.
|
| X | ||||||||||
- Details
|