Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Revenue (note 11)	$ 13,384		$ 20,462
Operating expenses:
Research and development	10,720	$ 8,205	22,511	$ 17,342
General and administrative	3,310	2,307	6,630	4,928
Total operating expenses	14,030	10,512	29,141	22,270
Loss from operations	(646)	(10,512)	(8,679)	(22,270)
Other income (expense):
Interest income	912	706	2,028	1,388
Interest expense	(154)	(365)	(484)	(723)
Foreign exchange gain	662	135	424	265
Loss on repayment of term loan (note 9)	(988)		(988)
Loss before income taxes	(214)	(10,036)	(7,699)	(21,340)
Income tax (expense) recovery (note 12)	39	29	40	(8)
Net loss and comprehensive loss	(175)	(10,007)	(7,659)	(21,348)
Net loss attributable to preferred shareholders	(5)	(380)	(222)	(810)
Net loss attributable to common shareholders	$ (170)	$ (9,627)	$ (7,437)	$ (20,538)
Net loss per common share (note 5):
Basic and diluted	$ 0.00	$ (0.37)	$ (0.22)	$ (0.80)
Weighted-average common shares outstanding (note 5):
Basic	34,979,282	25,773,879	34,084,508	25,763,858
Diluted	34,979,282	25,775,559	34,084,508	25,763,858