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Note 5 - Stockholders' Equity and Stock-based Compensation (Details Textual)	12 Months Ended
	Dec. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2023 shares
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)	14,679	14,583
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	396,096
Defined Benefit Plan, Plan Assets, Contributions by Employer \| $	$ 914,000	$ 876,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures (in shares)	0	0
Share-based Compensation Arrangement By Share-based Payment Award, Options, Outstanding and Exercisable, Grant Date Fair Value \| $	$ 0	$ 0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)	0
Non-Employee Board Member Stock Option and Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	13,626
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) \| $ / shares	$ 17.61
Non-Employee Board Member Stock Option and Restricted Stock [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	1 year
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	13,626
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) \| $ / shares	$ 17.61
Employee Deferred Stock Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	4 years	4 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	27,400	22,100
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) \| $ / shares	$ 19.43	$ 21.08
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount \| $	$ 853,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	3 years 3 months 18 days
Employee Deferred Stock Award [Member] \| Share-Based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
Employee Deferred Stock Award [Member] \| Share-Based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
Employee Deferred Stock Award [Member] \| Share-Based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
Employee Deferred Stock Award [Member] \| Share-Based Payment Arrangement, Tranche Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
Salaries and Benefits [Member]
Share-Based Payment Arrangement, Expense \| $	$ 688,000	$ 572,000
Employee Stock Purchase Plan [Member]
Minimum Hours Per Week Required To Participate In ESPP	15
Percentage Of Fair Market Value Of Common Stock Purchased At By Employees	85.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)			450,000
KSOP [Member]
Period Of Service Required To Be Eligible For KSOP (Month)	6 months
Stock Plan 1994 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	1,650,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	99,687