Note 11 - Stockholders' Equity - Stock Option Activity (Details) - $ / shares	12 Months Ended	24 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020
Outstanding, number of options, balance (in shares)	3,200,750	3,575,000	3,575,000
Outstanding, weighted average exercise price, balance (in dollars per share)	$ 0.45	$ 0.45	$ 0.45
Granted, number of options (in shares)	2,745,000	0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in CAD per share)	$ 0.33
Exercised, number of options (in shares)
Exercised, weighted average exercise price (in dollars per share)
Cancelled, number of options (in shares)	(70,000)	(374,250)
Cancelled, weighted average exercise price (in dollars per share)	$ (0.42)	$ (0.41)
Granted, weighted average exercise price (in dollars per share)	$ 0.33
Exercised, number of options (in shares)
Exercised, weighted average exercise price (in dollars per share)
Cancelled, weighted average exercise price (in dollars per share)	$ (0.42)	$ (0.41)
Outstanding, number of options, balance (in shares)	5,875,750	3,200,750	5,875,750
Outstanding, weighted average exercise price, balance (in dollars per share)	$ 0.39	$ 0.45	$ 0.39

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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