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Note 8 - Stock-based Compensation (Details Textual) - USD ($)	1 Months Ended	9 Months Ended
	Mar. 31, 2025	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)		290,000		383,000
The 2025 Employee Stock Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Discount from Market Price, Offering Date	5.00%
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	200,000	200,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Minimum Employee Payroll Deduction	$ 5
Share-Based Compensation Arrangement by Share-Based Payment Award, Maximum Employee Payroll Deduction	$ 200
The 2025 Employee Stock Purchase Plan [Member] | Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Purchase Price of Common Stock, Percent	95.00%
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		3 years
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		24,910
Noninterest Expense [Member]
Share-Based Payment Arrangement, Expense		$ 2,700,000	$ 2,500,000

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Maximum employee payroll deduction Share-Based Compensation Arrangement by Share-Based Payment Award, Minimum Employee Payroll Deduction

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