Condensed Consolidated Statement of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Common shares	Accumulated deficit	Accumulated other comprehensive loss	Additional paid-in capital
Beginning balance (in shares) at Dec. 31, 2020		46,035,389
Beginning balance at Dec. 31, 2020	$ 409,922	$ 724,219	$ (471,261)	$ (6,659)	$ 163,623
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common shares on exercise of options		78,736
Issuance of common shares on exercise of options	1,962	$ 2,624			(662)
Issuance of common shares through employee stock purchase plan		26,807
Issuance of common shares through employee stock purchase plan	1,321	$ 1,321
Issuance of common shares upon vesting of restricted stock units ("RSUs")		23,956
Issuance of common shares upon vesting of restricted stock units ("RSUs")	0	$ 843			(843)
Stock-based compensation expense (recovery)	8,530				8,530
Net loss	(44,590)		(44,590)
Ending balance (in shares) at Mar. 31, 2021		46,164,888
Ending balance at Mar. 31, 2021	$ 377,145	$ 729,007	(515,851)	(6,659)	170,648
Beginning balance (in shares) at Dec. 31, 2021	46,633,935	46,633,935
Beginning balance at Dec. 31, 2021	$ 249,094	$ 741,147	(683,104)	(6,659)	197,710
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common shares on exercise of options		2,112
Issuance of common shares on exercise of options	12	$ 20			(8)
Issuance of common shares through employee stock purchase plan		61,801
Issuance of common shares through employee stock purchase plan	1,361	$ 1,361
Issuance of common shares upon vesting of restricted stock units ("RSUs")		37,398
Issuance of common shares upon vesting of restricted stock units ("RSUs")	0	$ 1,382			(1,382)
Stock-based compensation expense (recovery)	(2,932)				(2,932)
Issuance of common shares and pre-funded warrants in connection with public offering, net of offering costs (notes 8a and 8d) (in shares)		11,035,000
Issuance of common shares and pre-funded warrants in connection with public offering, net of offering costs (notes 8a and 8d)	107,534	$ 82,549			24,985
Net loss	$ (72,625)		(72,625)
Ending balance (in shares) at Mar. 31, 2022	57,770,246	57,770,246
Ending balance at Mar. 31, 2022	$ 282,444	$ 826,459	$ (755,729)	$ (6,659)	$ 218,373