Note 3 - Investment Securities - Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Jul. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale, Amortized Cost	$ 418,935		$ 468,549
Securities available for sale, gross unrealized gains	374		787
Securities available for sale, gross unrealized losses	30,066		32,065
Securities available for sale, at fair value (amortized cost $418,935 and $468,549, respectively)	389,243		437,271
Securities held to maturity, amortized cost	7,000	$ 2,000	7,000
Securities held to maturity, gross unrealized gains	0		0
Securities held to maturity, gross unrealized losses	2,409		2,554
Debt Securities, Held-to-Maturity, Fair Value	4,591		4,446
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Debt Securities, Available-for-Sale, Amortized Cost	76,295		81,166
Securities available for sale, gross unrealized gains	0		0
Securities available for sale, gross unrealized losses	8,354		9,122
Securities available for sale, at fair value (amortized cost $418,935 and $468,549, respectively)	67,941		72,044
Agency Collateralized Mortgage Obligations [Member]
Debt Securities, Available-for-Sale, Amortized Cost	47,821		25,402
Securities available for sale, gross unrealized gains	197		94
Securities available for sale, gross unrealized losses	500		323
Securities available for sale, at fair value (amortized cost $418,935 and $468,549, respectively)	47,518		25,173
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost	122,834		138,174
Securities available for sale, gross unrealized gains	6		38
Securities available for sale, gross unrealized losses	4,760		8,707
Securities available for sale, at fair value (amortized cost $418,935 and $468,549, respectively)	118,080		129,505
US Treasury and Government [Member]
Debt Securities, Available-for-Sale, Amortized Cost	21,803		64,758
Securities available for sale, gross unrealized gains	0		0
Securities available for sale, gross unrealized losses	254		1,674
Securities available for sale, at fair value (amortized cost $418,935 and $468,549, respectively)	21,549		63,084
Municipal Notes [Member]
Debt Securities, Available-for-Sale, Amortized Cost	150,182		159,049
Securities available for sale, gross unrealized gains	171		655
Securities available for sale, gross unrealized losses	16,198		12,239
Securities available for sale, at fair value (amortized cost $418,935 and $468,549, respectively)	134,155		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	2,409		2,554
Debt Securities, Held-to-Maturity, Fair Value	$ 4,591		$ 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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