Note 12 - Stock-based Compensation (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Share-based Compensation, Tax Charges to Additional Paid in Capital From Exercise and Vesting	$ 0	$ 0
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 0		$ 0
Restricted Stock [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures (in shares)	9,003	206,629
Share-Based Payment Arrangement, Expensed and Capitalized, Amount	$ 400	$ 6,400
Share-Based Payment Arrangement, Expense	900	900
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 6,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	3 years 3 months 18 days
Restricted Stock [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Month)	12 months
Restricted Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Month)	60 months
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Expense	$ 0	$ 100
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)	10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period (in shares)	0	0
Employee Stock Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	500,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	41,169
The Fourth Amended 2014 Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	5,750,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	1,970,518

The value of tax charges to additional paid in capital from exercise and vesting under share-based compensation.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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