Nature of the business and basis of presentation- Liquidity (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Nature of business and basis of presentation
Net loss	$ 11,324	$ 6,503
Accumulated deficit	$ 111,874		$ 100,550

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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