Additional information on the consolidated statements of loss - Disclosure of detailed information about cost of sales (Details) - CAD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Additional Information On Consolidated Statements Of Loss Line Items
Cost of sales	$ 262,881	$ 371,305
Royalty interests [Member]
Additional Information On Consolidated Statements Of Loss Line Items
Cost of sales	272	245
Stream interests [Member]
Additional Information On Consolidated Statements Of Loss Line Items
Cost of sales	13,437	13,181
Offtake interests [Member]
Additional Information On Consolidated Statements Of Loss Line Items
Cost of sales	$ 249,172	$ 357,879

The amount of costs relating to expenses directly or indirectly attributed to the goods or services sold, which may include, but are not limited to, costs previously included in the measurement of inventory that has now been sold, unallocated production overheads and abnormal amounts of production costs of inventories.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_103&doctype=Standard
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