SHAREHOLDER'S CAPITAL - Contributed Surplus (Details) - CAD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
May 31, 2018	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019
SHAREHOLDER'S CAPITAL
Contributed surplus at beginning of period			$ 16.4	$ 2.0
Share-based compensation expense	$ 18.8	$ 2.0	37.9	14.5
Contributed surplus at end of period		$ 2.0	$ 54.3	$ 16.4

Share Capital, Reserves And Other Equity Interest [Abstract]

No definition available.

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- Definition

The amount received or receivable from the issuance of the entity's shares in excess of nominal value and amounts received from other transactions involving the entity's stock or stockholders.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 55
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-URIDate 2020-01-01

+ Details

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- Definition

The increase (decrease) in equity resulting from share-based payment transactions. [Refer: Equity]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 106
-Subparagraph d
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_106_d_iii&doctype=Standard
-URIDate 2020-01-01

+ Details

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