Significant Accounting Policies (Details) - Options Activity	9 Months Ended
Feb. 28, 2018 $ / shares shares
Options Activity [Abstract]
Outstanding May 31, 2017 \| shares	897,000
Outstanding May 31, 2017 \| $ / shares	$ 0.98
Granted \| shares	287,000
Granted \| $ / shares	$ 3.63
Exercised \| shares	(24,125)
Exercised \| $ / shares	$ 0.78
Cancelled or expired \| shares	(10,625)
Cancelled or expired \| $ / shares	$ 1.44
Outstanding February 28, 2018 \| shares	1,149,250
Outstanding February 28, 2018 \| $ / shares	$ 1.64

No definition available.

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- Definition

For presentations that combine terminations, 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 or that expired.

+ References

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- Definition

Weighted average price of options that were either forfeited or expired.

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- Definition

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

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

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 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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