SHAREHOLDERS' EQUITY - Normal Course Issuer Bid (Details) - 2020 NCIB - Class B Non-Voting Shares	Apr. 30, 2020 CAD ($) shares
Disclosure of classes of share capital [line items]
Authorized amount (in shares) \| shares	34,900,000
Authorized amount \| $	$ 500,000,000

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

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