Note 5 - Investment Securities (Tables)

12 Months Ended

Dec. 31, 2024

Notes Tables

Marketable Securities [Table Text Block]

	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

	December 31, 2023
	Amortized		Unrealized		Unrealized			Allowance for		Fair
(dollars in thousands)	Cost		Gains		Losses			Credit Losses		Value
Available-for-sale
U.S. Treasury and agencies	$	1,119	$	4	$	(3	)		—	$	1,120
Mortgage backed securities
Residential agency		524,140		1		(88,547	)		—		435,594
Commercial		1,476		—		(123	)		—		1,353
Asset backed securities		26		—		(1	)		—		25
Corporate bonds		57,993		—		(9,349	)		—		48,644
Total available-for-sale investment securities		584,754		5		(98,023	)		—		486,736
Held-to-maturity
Obligations of state and political agencies		129,603		—		(12,613	)		114		116,990
Mortgage backed securities
Residential agency		170,125		—		(28,498	)		99		141,627
Total held-to-maturity investment securities		299,728		—		(41,111	)		213		258,617
Total investment securities	$	884,482	$	5	$	(139,134	)	$	213	$	745,353

Schedule of Realized Gain (Loss) [Table Text Block]

	Year ended
	December 31,
(dollars in thousands)	2024		2023			2022
Proceeds	$	130,415	$	171,758		$	—
Realized gains		—		—			—
Realized losses		—		(24,643	)		—

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

			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

			December 31, 2023
			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	$	(3	)	$	489	$	—		$	—	$	(3	)	$	489
Mortgage backed securities
Residential agency		112		—			43		(88,547	)		435,505		(88,547	)		435,548
Commercial		1		—			—		(123	)		1,353		(123	)		1,353
Asset backed securities		3		—			—		(1	)		25		(1	)		25
Corporate bonds		12		—			—		(9,349	)		48,644		(9,349	)		48,644
Total available-for-sale investment securities		129	$	(3	)	$	532	$	(98,020	)	$	485,527	$	(98,023	)	$	486,059

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	$	6,801	$	6,730	$	14,976	$	14,980
Due after one year through five years		54,832		50,924		16,710		16,622
Due after five years through ten years		48,016		41,694		57,990		52,374
Due after 10 years		9,974		8,637		370		371
		119,623		107,985		90,046		84,347
Mortgage-backed securities
Residential agency		156,093		129,001		596,510		503,706
Total investment securities	$	275,716	$	236,986	$	686,556	$	588,053

Investment [Table Text Block]

	December 31,		December 31,
(dollars in thousands)	2024		2023
Federal Reserve	$	7,519	$	4,623
FHLB		13,656		16,566