Note 3 - Investment Securities (Tables)

6 Months Ended

Jun. 30, 2025

Notes Tables

Marketable Securities [Table Text Block]

	June 30, 2025
	Amortized		Unrealized		Unrealized			Allowance for		Fair
(dollars in thousands)	Cost		Gains		Losses			Credit Losses		Value
Available-for-sale
U.S. Treasury and agencies	$	638	$	—	$	(1	)	$	—	$	637
Mortgage backed securities
Residential agency		564,826		330		(76,217	)		—		488,939
Commercial		1,336		—		(56	)		—		1,280
Asset backed securities		17		—		—			—		17
Corporate bonds		53,982		—		(3,703	)		—		50,279
Total available-for-sale investment securities		620,799		330		(79,977	)		—		541,152
Held-to-maturity
Obligations of state and political agencies		114,141		—		(8,770	)		75		105,371
Mortgage backed securities
Residential agency		149,692		—		(23,559	)		52		126,133
Total held-to-maturity investment securities		263,833		—		(32,329	)		127		231,504
Total investment securities	$	884,632	$	330	$	(112,306	)	$	127	$	772,656

	December 31, 2024
	Amortized		Unrealized		Unrealized			Allowance for		Fair
(dollars in thousands)	Cost		Gains		Losses			Credit Losses		Value
Available-for-sale
U.S. Treasury and agencies	$	30,691	$	18	$	(2	)		—	$	30,707
Mortgage backed securities
Residential agency		596,510		1		(92,805	)		—		503,706
Commercial		1,350		—		(99	)		—		1,251
Asset backed securities		19		—		—			—		19
Corporate bonds		57,986		—		(5,616	)		—		52,370
Total available-for-sale investment securities		686,556		19		(98,522	)		—		588,053
Held-to-maturity
Obligations of state and political agencies		119,623		—		(11,638	)		77		107,985
Mortgage backed securities
Residential agency		156,093		—		(27,092	)		54		129,001
Total held-to-maturity investment securities		275,716		—		(38,730	)		131		236,986
Total investment securities	$	962,272	$	19	$	(137,252	)	$	131	$	825,039

Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block]

			June 30, 2025
			Less than 12 Months					Over 12 Months					Total
	Number of		Unrealized			Fair		Unrealized			Fair		Unrealized			Fair
(dollars in thousands)	Holdings		Losses			Value		Losses			Value		Losses			Value
Available-for-sale
U.S. Treasury and agencies		2	$	—		$	—	$	(1	)	$	469	$	(1	)	$	469
Mortgage backed securities
Residential agency		111		(1	)		35		(76,216	)		383,021		(76,217	)		383,056
Commercial		1		—			—		(56	)		1,278		(56	)		1,278
Asset backed securities		3		—			—		—			16		—			16
Corporate bonds		11		—			—		(3,703	)		50,279		(3,703	)		50,279
Total available-for-sale investment securities		128	$	(1	)	$	35	$	(79,976	)	$	435,063	$	(79,977	)	$	435,098

			December 31, 2024
			Less than 12 Months					Over 12 Months					Total
	Number of		Unrealized			Fair		Unrealized			Fair		Unrealized			Fair
(dollars in thousands)	Holdings		Losses			Value		Losses			Value		Losses			Value
Available-for-sale
U.S. Treasury and agencies		1	$	—		$	—	$	(2	)	$	327	$	(2	)	$	327
Mortgage backed securities
Residential agency		124		(1,715	)		116,800		(91,090	)		386,864		(92,805	)		503,664
Commercial		1		—			—		(99	)		1,251		(99	)		1,251
Asset backed securities		3		—			—		—			18		—			18
Corporate bonds		12		—			—		(5,616	)		52,370		(5,616	)		52,370
Total available-for-sale investment securities		141	$	(1,715	)	$	116,800	$	(96,807	)	$	440,830	$	(98,522	)	$	557,630

Investments Classified by Contractual Maturity Date [Table Text Block]

	Held-to-maturity				Available-for-sale
	Carrying		Fair		Amortized		Fair
(dollars in thousands)	Value		Value		Cost		Value
Due within one year or less	$	6,547	$	6,461	$	—	$	—
Due after one year through five years		57,083		53,878		1,625		1,568
Due after five years through ten years		43,077		38,521		53,999		50,296
Due after 10 years		7,434		6,511		349		349
		114,141		105,371		55,973		52,213
Mortgage-backed securities
Residential agency		149,692		126,133		564,826		488,939
Total investment securities	$	263,833	$	231,504	$	620,799	$	541,152

Investment [Table Text Block]

	June 30,		December 31,
(dollars in thousands)	2025		2024
Federal Reserve	$	8,631	$	7,519
FHLB		18,161		13,656