Condensed Consolidated Statements of Shareholders' Equity and Convertible Preferred Shares - USD ($) $ in Thousands	Common Shares	Additional paid-in capital	Cumulative translation adjustment	Accumulated deficit	Class A1 preferred shares	Class A2 preferred shares	Class B preferred shares	Class C preferred shares	Class D1 preferred shares	Class D2 preferred shares	Total
Balance at the beginning of period at Dec. 31, 2018	$ 2,039	$ 2,655	$ (1,634)	$ (58,270)							$ 83,548
Balance at the beginning of period (in shares) at Dec. 31, 2018	596,787
Temporary equity, balance at the beginning of period at Dec. 31, 2018					$ 2,027	$ 12,643	$ 17,198	$ 27,236	$ 64,719	$ 14,935
Temporary equity, balance at the beginning of period (in shares) at Dec. 31, 2018					372,211	2,443,914	2,830,907	3,786,878	6,893,236	1,223,656
Increase (Decrease) in Stockholders' Equity and Temporary Equity
Net loss and comprehensive loss				(10,452)							(10,452)
Exercise of stock options (note 4)	$ 51	(26)									25
Exercise of stock options (note 4) (in shares)	18,153
Share-based compensation (note 4)		211									211
Balance at the end of period at Mar. 31, 2019	$ 2,090	2,840	(1,634)	(68,722)							73,332
Balance at the end of period (in shares) at Mar. 31, 2019	614,940
Temporary equity, balance at the end of period at Mar. 31, 2019					$ 2,027	$ 12,643	$ 17,198	$ 27,236	$ 64,719	$ 14,935
Temporary equity, balance at the end of period (in shares) at Mar. 31, 2019					372,211	2,443,914	2,830,907	3,786,878	6,893,236	1,223,656
Balance at the beginning of period at Dec. 31, 2019	$ 226,245	3,805	(1,634)	(113,499)							$ 114,917
Balance at the beginning of period (in shares) at Dec. 31, 2019	24,505,748										24,505,748
Increase (Decrease) in Stockholders' Equity and Temporary Equity
Net loss and comprehensive loss				(16,343)							$ (16,343)
Exercise of stock options (note 4)	$ 133	(56)									77
Exercise of stock options (note 4) (in shares)	53,722
Share-based compensation (note 4)		981									981
Balance at the end of period at Mar. 31, 2020	$ 226,378	$ 4,730	$ (1,634)	$ (129,842)							$ 99,632
Balance at the end of period (in shares) at Mar. 31, 2020	24,559,470										24,559,470