The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_25&doctype=Standard
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2019-01-01
-Name IFRS
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-IssueDate 2018-01-01
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Convertible debenture

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Financial risks - Disclosure of detailed information about financial instruments (Details) - CAD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2016
Disclosure Of Financial Risks [Line Items]
Convertible debentures	$ 350,000	$ 350,000
Lease liabilities	10,126
Revolving credit facility	19,482	30,000
Financial liabilities	379,608
2020 [Member]
Disclosure Of Financial Risks [Line Items]
Lease liabilities	1,256
Revolving credit facility	2,630
Financial liabilities	17,891
2021 [Member]
Disclosure Of Financial Risks [Line Items]
Lease liabilities	1,256
Revolving credit facility	2,630
Financial liabilities	66,122
2022 [Member]
Disclosure Of Financial Risks [Line Items]
Lease liabilities	1,256
Revolving credit facility	2,630
Financial liabilities	315,886
2023 [Member]
Disclosure Of Financial Risks [Line Items]
Lease liabilities	1,261
Revolving credit facility	21,773
Financial liabilities	23,034
2024 [Member]
Disclosure Of Financial Risks [Line Items]
Lease liabilities	1,284
Revolving credit facility	0
Financial liabilities	1,284
2025-2029 [Member]
Disclosure Of Financial Risks [Line Items]
Lease liabilities	6,422
Revolving credit facility	0
Financial liabilities	6,422
Convertible debenture (2016) [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	50,000		$ 50,000
Convertible debenture (2016) [Member] \| 2020 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	2,005
Convertible debenture (2016) [Member] \| 2021 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	50,236
Convertible debenture (2016) [Member] \| 2022 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	0
Convertible debenture (2016) [Member] \| 2023 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	0
Convertible debenture (2016) [Member] \| 2024 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	0
Convertible debenture (2016) [Member] \| 2025-2029 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	0
Conv. debentures (2018) [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	300,000	$ 300,000
Conv. debentures (2018) [Member] \| 2020 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	12,000
Conv. debentures (2018) [Member] \| 2021 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	12,000
Conv. debentures (2018) [Member] \| 2022 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	312,000
Conv. debentures (2018) [Member] \| 2023 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	0
Conv. debentures (2018) [Member] \| 2024 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	0
Conv. debentures (2018) [Member] \| 2025-2029 [Member]
Disclosure Of Financial Risks [Line Items]
Convertible debentures	$ 0