Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands		Total		Convertible Preferred Shares [Member]	Common Shares [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]	[1]
Balance at Dec. 31, 2017		$ 35,934			$ 173,841	$ 36,471	$ (173,388)	$ (990)
Balance (in Shares) at Dec. 31, 2017					17,998,420
Net loss		(3,755)					(3,755)
Issued (cancelled) pursuant to exchange agreement (note 9b)				$ 21,825	$ (21,825)
Issued (cancelled) pursuant to exchange agreement (note 9b) (in Shares)				2,868,000	(2,868,000)
Cancelled pursuant to termination of collaboration agreement (note 9c)		(4,470)			$ (4,470)
Cancelled pursuant to termination of collaboration agreement (note 9c) (in Shares)					(1,000,000)
Stock-based compensation expense		670				670
Issued pursuant to exercise of stock options		119			$ 341	(222)
Issued pursuant to exercise of of stock options (in Shares)					40,881
Balance at Mar. 31, 2018		28,498		$ 21,825	$ 147,887	36,919	(177,143)	(990)
Balance (in Shares) at Mar. 31, 2018				2,868,000	14,171,301
Balance at Dec. 31, 2017		35,934			$ 173,841	36,471	(173,388)	(990)
Balance (in Shares) at Dec. 31, 2017					17,998,420
Net loss		$ (25,939)
Issued pursuant to exercise of of stock options (in Shares)	[2]	237,848
Balance at Sep. 30, 2018		$ 111,156		$ 11,932	$ 261,655	37,886	(199,327)	(990)
Balance (in Shares) at Sep. 30, 2018				1,568,000	25,187,441
Balance at Mar. 31, 2018		28,498		$ 21,825	$ 147,887	36,919	(177,143)	(990)
Balance (in Shares) at Mar. 31, 2018				2,868,000	14,171,301
Net loss		(7,801)					(7,801)
Issuance of common shares, net of issuance costs (note 9a)		28,957			$ 28,957
Issuance of common shares, net of issuance costs (note 9a) (in shares)					3,440,000
Stock-based compensation expense		657				657
Issued pursuant to exercise of stock options		63			$ 168	(105)
Issued pursuant to exercise of of stock options (in Shares)					29,650
Issuance of warrants		247				247
Balance at Jun. 30, 2018		50,621		$ 21,825	$ 177,012	37,718	(184,944)	(990)
Balance (in Shares) at Jun. 30, 2018				2,868,000	17,640,951
Net loss		(14,383)					(14,383)
Issuance of common shares, net of issuance costs (note 9a)		73,885			$ 73,885
Issuance of common shares, net of issuance costs (note 9a) (in shares)					6,100,000
Conversion of preferred shares to common shares (note 9b)				$ (9,893)	$ 9,893
Conversion of preferred shares to common shares (note 9b) (in Shares)				(1,300,000)	1,300,000
Stock-based compensation expense		662				662
Issued pursuant to exercise of stock options		$ 80			$ 865	(785)
Issued pursuant to exercise of of stock options (in Shares)		119,129	[2]		146,490
Issuance of warrants		$ 291				291
Balance at Sep. 30, 2018		111,156		$ 11,932	$ 261,655	37,886	(199,327)	(990)
Balance (in Shares) at Sep. 30, 2018				1,568,000	25,187,441
Balance at Dec. 31, 2018		103,295		$ 7,732	$ 265,923	38,515	(207,885)	(990)
Balance (in Shares) at Dec. 31, 2018				1,016,000	25,750,721
Cumulative effect of accounting change (note 3)		(175)					(175)
Net loss		(11,341)					(11,341)
Stock-based compensation expense		476				476
Issued pursuant to exercise of stock options		58			$ 117	(59)
Issued pursuant to exercise of of stock options (in Shares)					21,233
Balance at Mar. 31, 2019		92,313		$ 7,732	$ 266,040	38,932	(219,401)	(990)
Balance (in Shares) at Mar. 31, 2019				1,016,000	25,771,954
Balance at Dec. 31, 2018		103,295		$ 7,732	$ 265,923	38,515	(207,885)	(990)
Balance (in Shares) at Dec. 31, 2018				1,016,000	25,750,721
Net loss		$ (30,219)
Issued pursuant to exercise of of stock options (in Shares)	[2]	174,811
Balance at Sep. 30, 2019		$ 74,564		$ 7,732	$ 266,425	39,676	(238,279)	(990)
Balance (in Shares) at Sep. 30, 2019				1,016,000	25,868,594
Balance at Mar. 31, 2019		92,313		$ 7,732	$ 266,040	38,932	(219,401)	(990)
Balance (in Shares) at Mar. 31, 2019				1,016,000	25,771,954
Net loss		(10,007)					(10,007)
Stock-based compensation expense		470				470
Issued pursuant to exercise of stock options		11			$ 22	(11)
Issued pursuant to exercise of of stock options (in Shares)					3,102
Balance at Jun. 30, 2019		82,787		$ 7,732	$ 266,062	39,391	(229,408)	(990)
Balance (in Shares) at Jun. 30, 2019				1,016,000	25,775,056
Net loss		(8,871)					(8,871)
Stock-based compensation expense		630				630
Issued pursuant to exercise of stock options		$ 18			$ 363	(345)
Issued pursuant to exercise of of stock options (in Shares)		148,948	[2]		93,538
Balance at Sep. 30, 2019		$ 74,564		$ 7,732	$ 266,425	$ 39,676	$ (238,279)	$ (990)
Balance (in Shares) at Sep. 30, 2019				1,016,000	25,868,594

[1] Our accumulated other comprehensive loss is entirely related to historical cumulative translation adjustments from the application of U.S. dollar reporting when the functional currency of the Company was the Canadian dollar.

[2] During the nine months ended September 30, 2019, 23,625 stock options were exercised for the same number of common shares for cash (nine months ended September 30, 2018 – 41,507). In the same period, the Company issued 94,248 common shares (nine months ended September 30, 2018 – 103,189) for the cashless exercise of 151,186 stock options (nine months ended September 30, 2018 – 196,341).