v3.21.2

Equity transactions (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  |  |  |  |  |  | 1 Months Ended | 12 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 18, 2020 | Apr. 17, 2020 | Jan. 06, 2020 | Sep. 20, 2018 | Jun. 08, 2018 | Apr. 10, 2018 | Apr. 05, 2017 | Jan. 31, 2018 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Jun. 27, 2018 | Jun. 26, 2018 | Jun. 25, 2018 | Jan. 19, 2016 | Jan. 18, 2016 | Jan. 29, 2008
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock, Shares Authorized |  |  |  |  |  |  |  |  | 1,000,000 | 1,000,000 |  | 10,000,000 |  | 1,000,000 |  |  | 1,000,000
Preferred Stock, Shares Issued |  |  |  |  |  |  |  |  | 0 | 0 |  |  |  |  |  |  |
Preferred Stock, Shares Outstanding |  |  |  |  |  |  |  |  | 0 | 0 |  |  |  |  |  |  |
Ordinary shares issued to employees, directors and consultants |  |  | 80,000 |  |  | 180,000 |  |  |  |  |  |  |  |  |  |  |
Aggregate proceeds |  |  |  |  |  |  |  |  | $ 3,600 | $ 0 | $ 49,991 |  |  |  |  |  |
Number of Warrants, Exercised |  |  |  |  |  |  |  | 174,903 | (298,914) |  |  |  |  |  |  |  |
Common Stock, Par or Stated Value Per Share |  |  |  |  |  |  |  |  | $ 0.004 | $ 0.004 |  | $ 0.004 | $ 0.004 | $ 0.004 | $ 0.004 | $ 0.001 |
Allocated Share-based Compensation Expense |  |  |  |  |  | $ 194 |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value |  |  | $ 1.00 |  |  | $ 1.08 |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value |  |  |  |  |  |  |  |  | $ 1.20 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms |  |  |  |  |  |  |  |  |  | 1 year 3 months 4 days | 2 years 3 months 4 days |  |  |  |  |  |
Stock Purchase Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  | 4,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate proceeds |  | $ 3,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Price |  | $ 0.80 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Par or Stated Value Per Share |  | $ 0.004 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rights Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate proceeds |  |  |  | $ 50,160 |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of Stock, Number of Shares Issued in Transaction |  |  |  | 50,663,270 |  |  |  |  |  |  |  |  |  |  |  |  |
Sale of Stock, Price Per Share |  |  |  | $ 0.99 |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Offering Expense |  |  |  | $ 166 |  |  |  |  |  |  |  |  |  |  |  |  |
Chief Financial Officer [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures |  |  |  |  | 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Chief Technology Officer [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures |  |  |  |  | 500,000 |  |  |  |  |  |  |  |  |  |  |  |
Chief Executive Officer and Chief Technology Officer [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  |  |  |  |  |  | $ 600 | $ 600 | $ 340 |  |  |  |  |  |
Securities Purchase Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues | 4,500,000 |  |  |  |  |  | 434,783 |  |  |  |  |  |  |  |  |  |
Aggregate proceeds | $ 3,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant Purchase on Issue of Ordinary Shares |  |  |  |  |  |  | 326,087 |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right, Exercise Price of Warrants or Rights |  |  |  |  |  |  | $ 2.75 |  |  |  |  |  |  |  |  |  |
Securities Purchase Agreement, Warrants Issued percentage |  |  |  |  |  |  | 75.00% |  |  |  |  |  |  |  |  |  |

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