Income Taxes - Schedule of Income Tax Recovery (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Computed recoveries at Canadian federal and provincial tax rates	$ (11,237)	$ (9,314)
Change in valuation allowance	11,148	10,472
Investment tax credits earned	(1,522)	(1,567)
Tax attributes expired/utilized	678	911
Non-deductible expenditures	477	(472)
Other	433	(54)
Income tax recovery	$ (23)	$ (24)

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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