Liquidity and Uncertainties (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Liquidity and Uncertainties
Net loss	$ 15,080	$ 6,364
Accumulated deficit	$ 154,352		$ 139,272

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

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