Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenue	$ 1,549	$ 570
Operating expenses:
Research and development	16,130	8,329
General and administrative	8,153	5,293
Other operating expense, net	6,816	2,296
Total operating expenses	31,099	15,918
Operating loss	(29,550)	(15,348)
Interest expense, net	(1,938)	(1,309)
Net loss	$ (31,488)	$ (16,657)
Net loss per share attributable to holders of common stock:
Net loss per common share - basic and diluted	$ (2.23)	$ (1.39)
Weighted-average shares outstanding:
Weighted-average common shares used to compute basic and diluted net loss per common share	14,132,217	12,001,125