Note 3 - Business Combination - Allocation of the Purchase Price to the Fair Value of the Respective Assets and Liabilities Acquired (Details) - USD ($) $ in Thousands	Nov. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Business combination, goodwill acquired		$ 4,508	$ 0
Acquisition of Kindred BioSciences [Member]
Business combination, property and equipment acquired	$ 321
Business combination, goodwill acquired	4,508
Business Combination, Consideration Transferred, Total	$ 4,829

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
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