Note 10 - Subsequent Events (Details Textual) - Subsequent Event [Member] - Kronton Merger [Member] $ / shares in Units, $ in Millions	Oct. 24, 2023 USD ($) $ / shares
Sale of Stock, Price Per Share (in dollars per share) \| $ / shares	$ 1.9
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable \| $	$ 38.1

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 30
-Paragraph 8
-SubTopic 30
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479637/805-30-30-8

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 30
-Paragraph 7
-SubTopic 30
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479637/805-30-30-7

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