Stock options - Inputs (Details) - Stock options	12 Months Ended
May 31, 2019
Stock options
Volatility (as a percent)	70.00%
Forfeiture rate (as a percent)	0.00%
Dividend yield (as a percent)	0.00%
Minimum
Stock options
Risk-free rate (as a percent)	2.00%
Expected life (years)	3 years
Maximum
Stock options
Risk-free rate (as a percent)	2.08%
Expected life (years)	5 years

The forfeiture rate share options granted.

No definition available.

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- Definition

The expected option life of share options granted.

+ References

No definition available.

+ Details

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- Definition

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 47
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_47_a_i&doctype=Standard
-URIDate 2018-03-16

+ Details

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- Definition

The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

+ References

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The percentage of an expected dividend used to calculate the fair value of share options granted.

+ References

+ Details

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- Details

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