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Note 11 - Fair Value Measurement - Quantitative Information (Details) $ in Thousands	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Servicing rights on sold loans, at fair value	$ 2,999	$ 3,014
Fair Value, Recurring [Member]
Servicing rights on sold loans, at fair value	2,999	3,014
Assets, fair value	275,984	273,324
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Servicing rights on sold loans, at fair value	2,999	3,014	$ 3,301	$ 3,281
Assets, fair value	9,582	9,613
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Valuation Technique, Consensus Pricing Model [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Assets, fair value	$ 6,583	$ 6,599
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Valuation Technique, Consensus Pricing Model [Member] | Measurement Input, Quoted Price [Member] | Minimum [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Measurement input	98.3	99
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Valuation Technique, Consensus Pricing Model [Member] | Measurement Input, Quoted Price [Member] | Maximum [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Measurement input	100.2	100.4
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Sold Loan Servicing Rights [Member] | Valuation Technique, Discounted Cash Flow [Member]
Servicing rights on sold loans, at fair value	$ 2,999	$ 3,014
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Sold Loan Servicing Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Weighted Average [Member]
Sold loan servicing rights, measurement input	0.1125	0.1099
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Sold Loan Servicing Rights [Member] | Valuation Technique, Discounted Cash Flow [Member] | Measurement Input, Constant Prepayment Rate [Member] | Weighted Average [Member]
Sold loan servicing rights, measurement input	0.0542	0.0588

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Fair value portion of asset recognized for present right to economic benefit.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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