Note 12 - Capital Stock - Schedule of Outstanding Stock Options (Details) - $ / shares		3 Months Ended
Aug. 07, 2019	Oct. 31, 2019
Balance, number of stock options (in shares)		15,738,350
Balance, Weighted Average Exercise Price (in dollars per share)		$ 1.30
Granted, number of stock options (in shares)	597,650	597,650
Granted, Weighted Average Exercise Price (in dollars per share)	$ 0.91	$ 0.91
Expired, number of stock options (in shares)		(5,990,000)
Expired, Weighted Average Exercise Price (in dollars per share)		$ 1.34
Balance, number of stock options (in shares)		10,346,000
Balance, Weighted Average Exercise Price (in dollars per share)		$ 1.25

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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)(1)(iv)(4)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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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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