Note 6 - Share Capital - Summary of the Status of the Stock Option Plan (Details) - $ / shares	1 Months Ended	12 Months Ended
Apr. 30, 2019	Nov. 30, 2018	May 31, 2019	May 31, 2018
Number of Options, Balance (in shares)			9,861,900	8,846,900
Weighted Average Exercise Price, Balance (in CAD per share)			$ 0.85	$ 0.87
Number of Options, Granted (in shares)			4,920,000	1,840,000
Weighted Average Exercise Price, Granted (in CAD per share)			$ 2.06	$ 0.77
Number of Options, Exercised (in shares)	(615,000)	(4,036,900)	(4,651,900)	(256,660)
Weighted Average Exercise Price, Exercised (in CAD per share)	$ (1.40)	$ (0.86)	$ (0.93)	$ (0.66)
Number of Options, Forfeited (in shares)			(130,000)	(568,340)
Weighted Average Exercise Price, Forfeited (in CAD per share)			$ (1.81)	$ (0.93)
Number of Options, Balance (in shares)			10,000,000	9,861,900
Weighted Average Exercise Price, Balance (in CAD per share)			$ 1.40	$ 0.85

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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