Note 3 - Investment Securities - Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Available-for-Sale, Amortized Cost	$ 461,495	$ 468,549
Securities available for sale, gross unrealized gains	269	787
Securities available for sale, gross unrealized losses	33,620	32,065
Securities available for sale, at fair value	428,144	437,271
Securities held to maturity, amortized cost	7,000	7,000
Securities held to maturity, gross unrealized gains	0	0
Securities held to maturity, gross unrealized losses	2,595	2,554
Held-to-Maturity, Fair Value	4,405	4,446
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Available-for-Sale, Amortized Cost	77,981	81,166
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	9,511	9,122
Securities available for sale, at fair value	68,470	72,044
Agency Collateralized Mortgage Obligations [Member]
Available-for-Sale, Amortized Cost	48,276	25,402
Securities available for sale, gross unrealized gains	54	94
Securities available for sale, gross unrealized losses	613	323
Securities available for sale, at fair value	47,717	25,173
US Government Agencies Debt Securities [Member]
Available-for-Sale, Amortized Cost	135,931	138,174
Securities available for sale, gross unrealized gains	7	38
Securities available for sale, gross unrealized losses	8,671	8,707
Securities available for sale, at fair value	127,267	129,505
US Treasury and Government [Member]
Available-for-Sale, Amortized Cost	59,756	64,758
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	1,394	1,674
Securities available for sale, at fair value	58,362	63,084
Municipal Notes [Member]
Available-for-Sale, Amortized Cost	139,551	159,049
Securities available for sale, gross unrealized gains	208	655
Securities available for sale, gross unrealized losses	13,431	12,239
Securities available for sale, at fair value	126,328	147,465
Corporate Note Securities [Member]
Securities held to maturity, amortized cost	7,000	7,000
Securities held to maturity, gross unrealized gains	0	0
Securities held to maturity, gross unrealized losses	2,595	2,554
Held-to-Maturity, Fair Value	$ 4,405	$ 4,446

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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