RELATED PARTY TRANSACTIONS AND BALANCES - Schedule of transactions between related parties (Details) - CAD ($)	12 Months Ended
May 31, 2020	May 31, 2019
Disclosure of transactions between related parties [line items]
Salary or fees	$ 1,148,421	$ 1,067,296
Share-based payments	1,692,827	903,443
Total	2,841,248	1,970,739
Management
Disclosure of transactions between related parties [line items]
Salary or fees	977,284	907,230
Share-based payments	484,557	386,013
Total	1,461,841	1,293,243
Directors
Disclosure of transactions between related parties [line items]
Salary or fees	171,137	160,066
Share-based payments	1,208,270	517,430
Total	$ 1,379,407	$ 677,496

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

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The amount of compensation to key management personnel. [Refer: Key management personnel of entity or parent [member]]

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The amount of compensation to key management personnel in the form of share-based payments. [Refer: Key management personnel of entity or parent [member]]

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The amount of compensation to key management personnel in the form of short-term employee benefits. [Refer: Key management personnel of entity or parent [member]]

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