INCOME TAXES (Details 2) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Net loss before tax	$ (64,544)	$ (43,698)	$ (52,882)
Statutory combined US federal and state tax rate (2012 - statutory combined Canadian federal and provincial tax rate)	34.00%	39.83%	39.83%
Statutory federal and provincial taxes	$ (21,945)	$ (17,405)	$ (21,063)
Effect of change in valuation allowance	22,350	12,273	8,537
Non-deductible share-based compensation	923	930	1,085
Non-deductible warrant expenses for tax purposes	0	1,799	8,403
Tax credits	(1,814)	(180)	(96)
Share issue costs - temporary difference	(184)	(184)	(184)
Share issue costs - permanent difference	0	0	206
Differential in income tax rates of foreign subsidiary	31	3,047	3,059
Other differences	639	(280)	30
Income tax expense (benefit)	$ 0	$ 0	$ (23)

Effective Income Tax Rate Reconciliation, Combined Federal and State Statutory Income Tax Rate, Percent

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Represents the amount of 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 share issue costs.

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Income Tax Reconciliation, Share Issue Costs, Permanent Difference

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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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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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