Income Taxes - Statutory Income Tax Rates and Effective Tax Rates Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Loss from continuing operations before income taxes	$ (52,405)	$ (22,987)	$ (4,197)
Canadian statutory tax rates	26.00%	26.00%	26.00%
Expected income tax recovery	$ 13,625	$ 5,977	$ 1,091
Net decrease (increase) in valuation allowance	(13,684)	(2,486)	731
Non-taxable portion of capital gains	0	0	230
Investment tax credits	868	(222)	1,628
Stock-based compensation	(133)	(606)	(377)
Foreign rate differential	532	0	0
Non-taxable (deductible) expenditures	0	76	1,752
Changes in uncertain tax positions	0	(1,784)	(4,793)
Adjustments to capital losses for settlement of uncertain tax positions	0	(560)	0
Other	(1,673)	(417)	(70)
(Provision for) recovery of income taxes	$ (465)	$ (22)	$ 192

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Effective Income Tax Rate Reconciliation, Non-taxable Portion of Capita Gains

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

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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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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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 increase (decrease) in the valuation allowance for deferred tax assets.

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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 increase (decrease) in the income tax rates.

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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 income tax settlements. Including, but not limited to, domestic tax settlement, foreign tax settlement, state and local tax settlement, and other tax settlements.

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