Note 3 - Fair Value Measurements - Summary of Change in Estimated Fair VAlue of Level 3 Financial Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2022	Jun. 30, 2021
Reclass to additional paid-in-capital upon exercise			$ 8,590	$ 0
Warrant [Member]
Balance at January 1, 2022	$ 8,772	$ 0	0
Issuance of warrants		10,000
Change in fair value	182	(1,228)
Change in fair value	(182)	1,228
Reclass to additional paid-in-capital upon exercise	(8,590)
Balance at June 30, 2022	$ 0	$ 8,772	$ 0

Amount of increase to additional paid in capital (APIC) resulting from the exercising of warrants.

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ 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 (c)(1)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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- Definition

Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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