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Note 11 - Fair Value Measurement - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	$ 272,985	$ 270,310
Sold loan servicing rights, at fair value	2,999	3,014
Fair Value, Recurring [Member]
Sold loan servicing rights, at fair value	2,999	3,014
Total assets measured at fair value	275,984	273,324
Fair Value, Recurring [Member] | Derivative Financial Instruments, Assets [Member]
Interest rate swap derivative		1,703
Fair Value, Recurring [Member] | Derivative Financial Instruments, Liabilities [Member]
Interest rate swap derivative	871
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Sold loan servicing rights, at fair value	0	0
Total assets measured at fair value	13,849	13,885
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | Derivative Financial Instruments, Assets [Member]
Interest rate swap derivative		0
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | Derivative Financial Instruments, Liabilities [Member]
Interest rate swap derivative	0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Sold loan servicing rights, at fair value	0	0
Total assets measured at fair value	252,553	249,826
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] | Derivative Financial Instruments, Assets [Member]
Interest rate swap derivative		1,703
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] | Derivative Financial Instruments, Liabilities [Member]
Interest rate swap derivative	871
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Sold loan servicing rights, at fair value	2,999	3,014	$ 3,301	$ 3,281
Total assets measured at fair value	9,582	9,613
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Derivative Financial Instruments, Assets [Member]
Interest rate swap derivative		0
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Derivative Financial Instruments, Liabilities [Member]
Interest rate swap derivative	0
US States and Political Subdivisions Debt Securities [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	79,565	80,252
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	79,565	80,252
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	11,884	11,908
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	67,681	68,344
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
US Government Agencies Debt Securities [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	11,632	11,943
US Government Agencies Debt Securities [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	11,632	11,943
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	11,632	11,943
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
Corporate Issued Asset-backed Securities [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	7,676	7,961
Corporate Issued Asset-backed Securities [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	7,676	7,961
Corporate Issued Asset-backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
Corporate Issued Asset-backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	7,676	7,961
Corporate Issued Asset-backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
Corporate Debt Securities [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	37,392	38,801
Corporate Debt Securities [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	37,392	38,801
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	1,965	1,977
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	35,427	36,824
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
US Small Business Administration Securities [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	5,820	6,293
US Small Business Administration Securities [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	5,820	6,293
US Small Business Administration Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
US Small Business Administration Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	5,820	6,293
US Small Business Administration Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	97,968	91,656
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	97,968	91,656
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	97,968	91,656
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	32,932	33,404
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	32,932	33,404
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	0	0
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	26,349	26,805
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	$ 6,583	$ 6,599

X

- Definition

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

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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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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