Supplemental Information - Change in Non-Cash Working Capital Items (Details) - CAD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Additional information [abstract]
Trade and other receivables	$ 66,285	$ (62,198)
Trade and other payables	(51,499)	(50,660)
Trade and other receivables/payables	14,786	(112,858)
Changes in non-cash working capital related to:
Change in non-cash working capital	48,758	(52,070)
Investing activities	(32,031)	(62,485)
Foreign currency translation on non-cash working capital	(1,941)	1,697
Changes in non-cash working capital	$ 14,786	$ (112,858)

Adjustments For Increase (Decrease) In Trade And Other Receivables And Payables

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Foreign Currency Translation On Non-Cash Working Capital

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Increase (Decrease) In Non-Cash Working Capital

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Increase (Decrease) In Non-Cash Working Capital [Abstract]

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Increase (Decrease) In Non-Cash Working Capital, Investing Activities

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Adjustments for decrease (increase) in trade and other receivables to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Trade and other receivables; Profit (loss)]

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 7
-IssueDate 2020-01-01
-Paragraph 20
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2020-en-r&anchor=para_20&doctype=Standard
-URIDate 2020-01-01

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Adjustments for increase (decrease) in trade and other payables to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Trade and other payables; Profit (loss)]

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The increase (decrease) in working capital.

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