Consolidated Statement 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, 2016	$ 63,901			$ 173,246	$ 34,326	$ (142,681)	$ (990)
Balance (in Shares) at Dec. 31, 2016				17,930,590
Net loss	(30,704)					(30,704)
Stock-based compensation expense	2,460				2,460
Issued pursuant to exercise of stock options	177			$ 595	(415)	(3)
Issued pursuant to exercise of stock options (in Shares)				67,830
Issuance of warrants	100				100
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	(11,556)					(11,556)
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
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	1,327				1,327
Issued pursuant to exercise of stock options	$ 182			$ 509	(327)
Issued pursuant to exercise of stock options (in Shares)	118,719	[2]		70,531
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

[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 six months ended June 30, 2018, 36,007 stock options were exercised for the same number of common shares for cash (six months ended June 30, 2017 – 63,425). In the same period, the Company issued 34,524 common shares (six months ended June 30, 2017 – 4,405) for the cashless exercise of 82,712 stock options (six months ended June 30, 2017 – 7,581).