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Note 5 - Share-Based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)	4,641,685		4,641,685		4,385,477
Share Price (in dollars per share)	$ 1.7		$ 1.7
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 3.72		$ 3.72		$ 4.54
Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			4 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)			10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	9,098,000		9,098,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	4,370,364		4,370,364
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 100		$ 100
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 3.72		$ 3.72
Equity Incentive Plan [Member] \| Performance Based Stock Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)	993,835		993,835
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 3,400		$ 3,400
Share-Based Payment Arrangement, Expense	20	$ 40	40	$ 80
Equity Incentive Plan [Member] \| Non Performance Based Options [Member]
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 1,600		$ 1,600
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year