Note 6 - Share Based Compensation - Service Based Options Granted During Period (Details) - $ / shares	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Granted, number of options (in shares)	500,000	765,000
Weighted average grant date fair value (in dollars per share)	$ 2.09	$ 1.82
Granted, weighted average exercise price per share (in dollars per share)	$ 2.94	$ 2.60

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

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