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Note 8 - Stock-based Compensation (Details Textual) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2021
Stock or Unit Option Plan Expense	$ 24,000	$ 32,000	$ 100,000	$ 100,000
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	200,000		$ 200,000
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			2 years 2 months 12 days
Restricted Stock and Restricted Stock Units [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			3 years 8 months 12 days
Share-Based Payment Arrangement, Expense	500,000	$ 500,000	$ 900,000	$ 900,000
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 5,900,000		$ 5,900,000
Key Personnel [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)			10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)			0	0
Key Personnel [Member] \| Share-Based Payment Arrangement, Option [Member] \| Share-Based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			20.00%
Non-employee Directors and Certain Officers [Member] \| Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			2 years
Non-employee Directors and Certain Officers [Member] \| Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			5 years
Employees [Member] \| Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Requisite Service Period (Year)			5 years
A 2017 Long Term Incentive Compensation Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	1,800,000		1,800,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)			600,000		600,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	718,429		718,429