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Note 11 - Stock-based Compensation (Details Textual) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	May 17, 2018
Share-Based Payment Arrangement, Expense	$ 583,000	$ 464,000	$ 1,600,000	$ 1,200,000
Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year)			6 years 2 months 12 days		6 years 3 months 18 days
The 2018 Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)						1,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expected Contractual Term Forfeiture Rate			3.10%
The 2018 Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Tranche One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			1 year
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year)			5 years 6 months
The 2018 Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Tranche Two [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, Fair Value Assumptions, Expected Term (Year)			6 years 3 months
The 2018 Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Tranche Three [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year)			6 years 6 months
The 2018 Equity Incentive Plan [Member] | Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)						326,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	500		500
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 3,700,000		$ 3,700,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			2 years
The 2018 Equity Incentive Plan [Member] | Restricted Stock [Member] | Officers And Employees [Member] | Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			4 years
The 2018 Equity Incentive Plan [Member] | Restricted Stock [Member] | Officers And Employees [Member] | Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			5 years
The 2018 Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	52,060		52,060
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)			10 years
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 3,100,000		$ 3,100,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			2 years
The 2018 Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)			10 years
The 2018 Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Director [Member] | Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			1 year
The 2018 Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Officers And Employees [Member] | Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			4 years
The 2018 Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Officers And Employees [Member] | Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			5 years

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+ References

No definition available.

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+ References

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