Note 3 - Investment Securities - Summary of Continuous Unrealized Loss Position for Securities Classified as AFS (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Less than 12 Months, Fair Value	$ 3,415	$ 5,526
Less than 12 Months, Unrealized Losses	(52)	(491)
12 Months or More, Fair Value	311,548	329,283
12 Months or More, Unrealized Losses	(49,389)	(57,207)
Fair Value	314,963	334,809
Unrealized Losses	(49,441)	(57,698)
US Government Corporations and Agencies Securities [Member]
Less than 12 Months, Fair Value	280	1,268
Less than 12 Months, Unrealized Losses	(1)	(7)
12 Months or More, Fair Value	7,635	9,284
12 Months or More, Unrealized Losses	(265)	(433)
Fair Value	7,915	10,552
Unrealized Losses	(266)	(440)
US States and Political Subdivisions Debt Securities [Member]
Less than 12 Months, Fair Value	1,608	0
Less than 12 Months, Unrealized Losses	(24)	0
12 Months or More, Fair Value	13,698	15,425
12 Months or More, Unrealized Losses	(1,846)	(2,076)
Fair Value	15,306	15,425
Unrealized Losses	(1,870)	(2,076)
Corporate Debt Securities [Member]
Less than 12 Months, Fair Value	252	468
Less than 12 Months, Unrealized Losses	(4)	(28)
12 Months or More, Fair Value	25,447	25,888
12 Months or More, Unrealized Losses	(2,619)	(3,713)
Fair Value	25,699	26,356
Unrealized Losses	(2,623)	(3,741)
Residential Mortgage-Backed Securities [Member]
Less than 12 Months, Fair Value	0	2,705
Less than 12 Months, Unrealized Losses	0	(421)
12 Months or More, Fair Value	219,078	228,415
12 Months or More, Unrealized Losses	(37,261)	(42,498)
Fair Value	219,078	231,120
Unrealized Losses	(37,261)	(42,919)
Commercial Mortgage-Backed Securities [Member]
Less than 12 Months, Fair Value	1,275	1,085
Less than 12 Months, Unrealized Losses	(23)	(35)
12 Months or More, Fair Value	45,690	50,271
12 Months or More, Unrealized Losses	(7,398)	(8,487)
Fair Value	46,965	51,356
Unrealized Losses	$ (7,421)	$ (8,522)