v3.21.2

Summary of significant accounting policies (Revenue by major product line and Foreign Currency translation) (Details) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2016 | Dec. 31, 2015
Revenues | $ 4,293 | $ 5,115 | $ 1,570 |  |
Foreign exchange | 6.52 | 6.98 |  | 1.00 |
Foreign Currency Exchange Rate | 6.90 | 6.89 | 6.64 |  | 1.00
Maximum [Member] |  |  |  |  |
Foreign exchange | 0.77 |  |  |  |
Foreign Currency Exchange Rate | 0.73 |  |  |  |
Minimum [Member] |  |  |  |  |
Foreign exchange | 1.00 |  |  |  |
Foreign Currency Exchange Rate | 1.00 |  |  |  |
Interest On Loans [Member] |  |  |  |  |
Revenues | $ 1,667 | $ 3,930 | $ 980 |  |
Property lease and management |  |  |  |  |
Revenues | 1,130 | $ 1,185 | $ 590 |  |
Financial technology solution and services (Member) |  |  |  |  |
Revenues | $ 1,496 |  |  |  |

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