Note 7 - Research Grants and Agreements (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Research and Development Expense	$ 6,741	$ 5,829
Old Dominion University Research Foundation [Member] \| Sponsored Research Agreement SRA [Member]
Research and Development Expense	$ 0	$ 0

Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 985
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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