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Note 2 - Summary of Significant Accounting Policies - Assumptions Used to Estimate the Fair Value of the Forward Liability (Details)	Dec. 31, 2021	Dec. 31, 2020
Measurement Input, Discount for Lack of Marketability [Member] | Valuation Technique, Discounted Cash Flow [Member]
Forward contract	10	10
Measurement Input, Price Volatility [Member] | Valuation Technique, Discounted Cash Flow [Member]
Forward contract	85	80
Measurement Input, Weighted Average Cost of Capital [Member] | Valuation Technique, Discounted Cash Flow [Member]
Forward contract	14.5	15.3
Measurement Input, Probability of Achieving Contingent Target [Member] | Valuation Technique, Probability-based Valuation Approach [Member]
Forward contract	90	100

X

- Definition

Value of input used to measure net derivative asset (liability).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

+ Details

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