SHARE-BASED COMPENSATION PLANS - Options Fair Value Measurements (Details)	12 Months Ended
Dec. 31, 2018 CAD ($) year day	Dec. 31, 2017 CAD ($) year
Disclosure of terms and conditions of share-based payment arrangement [line items]
Maximum term of options granted	5 years
Share price (in CAD per share)	$ 1.48	$ 4.27
Exercise price (in CAD per share)	$ 1.48	$ 4.55
Risk free interest rate (%)	2.00%	0.90%
Option life (years) \| year	2.8	2.8
Option volatility (%)	65.00%	71.00%
Weighted average fair value of each share option granted (in CAD per share)	$ 0.64	$ 1.87
Bottom of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Forfeiture rate	3.00%	3.00%
Top of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Forfeiture rate	10.00%	10.00%
Share Options
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of trading days to determine weighted average trading price for options granted \| day	5
Share Options \| Tranche One
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting percentage	33.33%
Share Options \| Tranche Two
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting percentage	33.33%
Share Options \| Tranche Three
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting percentage	33.33%

Forfeiture Rate, Share Options Granted

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- Definition

Maximum Term Of Options Granted For Share-based Payment Arrangement

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Number Of Trading Days To Determine Weighted Average Trading Price

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Vesting Percentage For Share-based Payment Arrangements

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- Definition

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 47
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_47_a_i&doctype=Standard
-URIDate 2018-03-16

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The option life of share options granted.

+ References

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The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

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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

The weighted average exercise price of share options exercised in a share-based payment arrangement. [Refer: Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 45
-Subparagraph b
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_45_b_iv&doctype=Standard
-URIDate 2018-03-16

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- Definition

The weighted average fair value of share options granted during the period at the measurement date. [Refer: Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 47
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_47_a&doctype=Standard
-URIDate 2018-03-16

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- Definition

The weighted average share price used as input to the option pricing model to calculate the fair value of share options granted. [Refer: Option pricing model [member]; Weighted average [member]]

+ References

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