Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of Income Tax (Recovery) Expense

Income tax (recovery) expense varies from the amounts that would be computed by applying the expected Canadian and provincial statutory income tax rate of 26% (2016 – 26%, 2015 – 26%) to loss before income taxes as shown in the following table:

	2017			2016			2015
Computed recoveries at Canadian federal and provincial tax rates	$	(8,000	)	$	(5,980	)	$	(4,095	)
Change in valuation allowance		9,210			6,897			2,482
Investment tax credits earned		(1,393	)		(1,500	)		(1,220	)
Tax attributes expired/utilized		683			617			2,851
Non-deductible expenditures		594			569			977
Financing fees in equity		—			(531	)		—
Effect of tax rate increases		(1,444	)		—			—
Other		350			(72	)		(995	)
Income tax (recovery) expense	$	—		$	—		$	—

Schedule of Net Deferred Income Tax Assets

The significant components of the Company’s net deferred income tax assets are as follows:

	2017			2016
Deferred income tax assets
Scientific research and experimental development pool	$	25,056		$	22,823
Investment tax credits		22,872			22,483
Non-capital losses		13,645			7,800
Depreciable assets		5,360			4,163
Deferred financing fees		578			1,020
Other		114			126
Less - valuation allowance		(67,625	)		(58,415	)
Net deferred income tax assets	$	—		$	—