Taxes - Reconciliation of Expected Provision for Income Tax Expense/Recovery (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Earnings (loss) before income taxes	$ 20,624	$ (18,172)
Expected income tax expense (recovery) at Canadian statutory income tax rate of 26.5% (2013 - 26.5%)	5,465	(4,815)
Permanent differences	2,814	1,126
Effect of change in tax rates		90
Effect of unused tax credits		667
Foreign withholding taxes paid	212us-gaap_CurrentForeignTaxExpenseBenefit	84us-gaap_CurrentForeignTaxExpenseBenefit
Foreign rate differential	(918)	(588)
Increase (decrease) in valuation allowance	3,340	3,357
Provision for income tax recovery	$ 10,913us-gaap_IncomeTaxExpenseBenefit	$ (79)us-gaap_IncomeTaxExpenseBenefit

Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and 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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