Note 4 - Investment Securities (Tables)

12 Months Ended

Dec. 31, 2024

Notes Tables

Debt Securities, Available-for-Sale [Table Text Block]

			Gross		Gross
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
	(dollars in thousands)
December 31, 2024
Investment securities available-for-sale
Federal agency obligations	$	96,165	$	179	$	(11,674	)	$	84,670
Residential mortgage pass-through securities		439,445		211		(60,818	)		378,838
Commercial mortgage pass-through securities		24,989		-		(4,097	)		20,892
Obligations of U.S. states and political subdivisions​​		141,775		89		(19,460	)		122,404
Corporate bonds and notes		5,000		5		(18	)		4,987
Asset-backed securities		892		-		(7	)		885
Other securities		171		-		-			171
Total investment securities available-for-sale	$	708,437	$	484	$	(96,074	)	$	612,847

			Gross		Gross
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
	(dollars in thousands)
December 31, 2023
Investment securities available-for-sale
Federal agency obligations	$	55,898	$	189	$	(10,761	)	$	45,326
Residential mortgage pass-through securities		462,004		620		(51,433	)		411,191
Commercial mortgage pass-through securities		25,240		-		(3,676	)		21,564
Obligations of U.S. states and political subdivisions​​		148,795		415		(16,505	)		132,705
Corporate bonds and notes		5,000		-		(27	)		4,973
Asset-backed securities		1,260		-		(22	)		1,238
Other securities		165		-		-			165
Total investment securities available-for-sale	$	698,362	$	1,224	$	(82,424	)	$	617,162

Investments Classified by Contractual Maturity Date [Table Text Block]

	December 31, 2024
	Amortized		Fair
	Cost		Value
	(dollars in thousands)
Investment securities available-for-sale:
Due in one year or less	$	4,034	$	4,040
Due after one year through five years		5,304		5,282
Due after five years through ten years		10,400		9,132
Due after ten years		224,094		194,492
Residential mortgage pass-through securities		439,445		378,838
Commercial mortgage pass-through securities		24,989		20,892
Other securities		171		171
Total investment securities available-for-sale	$	708,437	$	612,847

Unrealized Gain (Loss) on Investments [Table Text Block]

	December 31, 2024
	Total					Less than 12 Months					12 Months or Longer
	Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
	Value		Losses			Value		Losses			Value		Losses
	(dollars in thousands)
Investment securities available-for-sale:
Federal agency obligation	$	53,467	$	(11,674	)	$	18,471	$	(60	)	$	34,996	$	(11,614	)
Residential mortgage pass-through securities		364,971		(60,818	)		26,809		(604	)		338,162		(60,214	)
Commercial mortgage pass-through securities		20,892		(4,097	)		-		-			20,892		(4,097	)
Obligations of U.S. states and political subdivisions		112,523		(19,460	)		13,281		(322	)		99,242		(19,138	)
Corporate bonds and notes		1,982		(18	)		1,982		(18	)		-		-
Asset-backed securities		885		(7	)		-		-			885		(7	)
Total temporarily impaired securities	$	554,720	$	(96,074	)	$	60,543	$	(1,004	)	$	494,177	$	(95,070	)

	December 31, 2023
	Total					Less than 12 Months					12 Months or Longer
	Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
	Value		Losses			Value		Losses			Value		Losses
	(dollars in thousands)
Investment securities available-for-sale:
Federal agency obligation	$	40,779	$	(10,761	)	$	1,689	$	(65	)	$	39,090	$	(10,696	)
Residential mortgage pass-through securities		382,042		(51,433	)		4,138		(51	)		377,904		(51,382	)
Commercial mortgage pass-through securities		21,565		(3,676	)		-		-			21,565		(3,676	)
Obligations of U.S. states and political subdivisions		101,189		(16,505	)		1,340		(7	)		99,849		(16,498	)
Corporate bonds and notes		4,973		(27	)		2,993		(7	)		1,980		(20	)
Asset-backed securities		1,238		(22	)		-		-			1,238		(22	)
Total temporarily impaired securities	$	551,786	$	(82,424	)	$	10,160	$	(130	)	$	541,626	$	(82,294	)