Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 740
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-Section 50
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to research tax credit.

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Expiration date of the tax credit carryforward, in CCYY-MM-DD format.

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Amount of unrecognized tax benefits.

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Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Tax Credit Carryforward [Line Items]
Income tax (recovery) expense	26.00%	26.00%	26.00%
Unclaimed Tax Deductions Related To Scientific Research And Experimental Development Expenditures	$ 87,781	$ 81,107
Non-capital losses carried forward for tax purposes	$ 29,999	16,285
Tax Credit Carry forward, Expiration Date	Dec. 31, 2036
Unrecognized tax benefits of uncertain tax positions	$ 6,350	6,350
Canada Revenue Agency [Member] \| Latest Tax Year [Member]
Tax Credit Carryforward [Line Items]
Tax year open for income tax examination	2003
Canada Revenue Agency [Member] \| Earliest Tax Year [Member]
Tax Credit Carryforward [Line Items]
Tax year open for income tax examination	2015
Investment Tax credit [Member]
Tax Credit Carryforward [Line Items]
Tax credit available to offset federal taxes payable	$ 20,160	18,875
Provincial Tax Credit [Member]
Tax Credit Carryforward [Line Items]
Tax credit available to offset federal taxes payable	$ 7,624	$ 7,385