SHARE CAPITAL (Detail) - Fair Values of Non-Employee Stock Options - USD ($)	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019
Share-based Payment Arrangement [Abstract]
Fair value of non-employee options, beginning of the year	$ 6,191	$ 205,120
Fair value of options granted		(23,040)
Fair value of options on vesting	1,820	3,502
Change in fair value of non-employee stock options during the year	8,530	(179,391)
Fair value of non-employee options, end of the year	$ 16,541	$ 6,191

No definition available.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ 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=116856206&loc=d3e5070-113901

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ 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
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

+ 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
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Value, before forfeiture, of shares granted under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

+ References

No definition available.

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