Note 8 - Stock-based Compensation (Details Textual) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026 USD ($) shares	Jun. 30, 2026 USD ($) shares
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount \| $	$ 1.7	$ 1.7
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		2 years 8 months 12 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant	4,063,187	4,063,187
Amended ESPP [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant	266,039	266,039
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation	21,462	41,218

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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