FINANCIAL INSTRUMENTS - Fair Value Inputs (Details) - 7% Convertible Debentures embedded derivative	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Risk premium	7.90%	12.90%
Borrowing costs	15.00%	10.00%
Expected volatility	45.00%	45.00%
Remaining life (years)	3 years 7 months 6 days	4 years 7 months 6 days

Remaining Life, Significant Unobservable Inputs, Liabilities

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- Definition

Risk Premium. Significant Unobservable Inputs, Liabilities

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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- Definition

Historical volatility for shares used as a significant Level 3 unobservable input for liabilities. [Refer: Level 3 of fair value hierarchy [member]]

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Weighted average cost of capital used as a significant Level 3 unobservable input for liabilities. [Refer: Level 3 of fair value hierarchy [member]; Weighted average [member]]

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