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Note 13 - Fair Value Measurement - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	$ 310,860		$ 295,623
Sold loan servicing rights	3,584		3,793
Fair Value, Recurring [Member]
Sold loan servicing rights	3,584		3,793
Equity and partnership investments	14,412		13,183
Total assets measured at fair value	328,856		312,599
Fair Value, Recurring [Member] \| Derivative Financial Instruments, Assets [Member]
Interest rate swap derivative	2,749
Fair Value, Recurring [Member] \| Derivative Financial Instruments, Liabilities [Member]
Interest rate swap derivative			1,002
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Sold loan servicing rights	0		0
Equity and partnership investments	0		0
Total assets measured at fair value	6,999		7,001
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	0		0
Equity and partnership investments	1,762		0
Total assets measured at fair value	288,528		261,153
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Derivative Financial Instruments, Assets [Member]
Interest rate swap derivative	2,749
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Derivative Financial Instruments, Liabilities [Member]
Interest rate swap derivative			1,002
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Sold loan servicing rights	3,584	$ 3,740	3,793	$ 3,729	$ 3,825	$ 3,887
Equity and partnership investments	12,650		13,183
Total assets measured at fair value	33,329		44,445
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 $341,011 and $333,950, respectively)	81,363		87,761
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	81,363		87,761
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 $341,011 and $333,950, respectively)	5,054		5,118
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 $341,011 and $333,950, respectively)	76,309		82,643
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 $341,011 and $333,950, respectively)	0		0
US Government Agencies Debt Securities [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	13,296		11,782
US Government Agencies Debt Securities [Member] \| Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	13,296		11,782
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 $341,011 and $333,950, 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 $341,011 and $333,950, respectively)	13,296		11,782
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 $341,011 and $333,950, respectively)	0		0
Corporate Issued Asset-backed Securities [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	16,391		5,286
Corporate Issued Asset-backed Securities [Member] \| Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	16,391		5,286
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 $341,011 and $333,950, 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 $341,011 and $333,950, respectively)	16,391		5,286
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 $341,011 and $333,950, respectively)	0		0
Corporate Debt Securities [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	54,058		51,454
Corporate Debt Securities [Member] \| Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	54,058		51,454
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 $341,011 and $333,950, respectively)	1,945		1,883
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 $341,011 and $333,950, respectively)	52,113		49,571
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 $341,011 and $333,950, respectively)	0		0
US Small Business Administration Securities [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	9,317
US Small Business Administration Securities [Member] \| Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	9,317
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 $341,011 and $333,950, respectively)	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 $341,011 and $333,950, respectively)	9,317
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 $341,011 and $333,950, respectively)	0
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	78,549		63,247
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 $341,011 and $333,950, respectively)	78,549		63,247
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 $341,011 and $333,950, 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 $341,011 and $333,950, respectively)	78,549		63,247
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 $341,011 and $333,950, respectively)	0		0
Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	57,886		76,093
Mortgage-Backed Securities, Issued by Private Enterprises [Member] \| Fair Value, Recurring [Member]
Investment securities available for sale, at fair value (amortized cost of $341,011 and $333,950, respectively)	57,886		76,093
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 $341,011 and $333,950, 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 $341,011 and $333,950, respectively)	40,791		48,624
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 $341,011 and $333,950, respectively)	$ 17,095		$ 27,469