Note 4 - Debt and Equity Securities (Tables)

9 Months Ended

Sep. 30, 2020

Notes Tables

Marketable Securities [Table Text Block]

	September 30, 2020
	Securities Available-For-Sale
	In Thousands
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Market Value
U.S. Government-sponsored enterprises (GSEs)	$	116,457	$	429	$	78	$	116,808
Mortgage-backed securities		296,845		6,877		607		303,115
Asset-backed securities		26,717		495		133		27,079
Corporate bonds		2,500		11		—		2,511
Obligations of states and political subdivisions		122,590		3,253		353		125,490
	$	565,109	$	11,065	$	1,171	$	575,003

	December 31, 2019
	Securities Available-For-Sale
	In Thousands
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Market Value
U.S. Government-sponsored enterprises (GSEs)	$	59,735	$	48	$	204	$	59,579
Mortgage-backed securities		265,648		2,300		635		267,313
Asset-backed securities		27,531		1		303		27,229
Corporate bonds		—		—		—		—
Obligations of states and political subdivisions		67,293		559		828		67,024
	$	420,207	$	2,908	$	1,970	$	421,145

Investments Classified by Contractual Maturity Date [Table Text Block]

	Available-For-Sale
	In Thousands
	Amortized Cost		Estimated Market Value
Due in one year or less	$	1,662	$	1,663
Due after one year through five years		42,049		42,662
Due after five years through ten years		125,488		127,325
Due after ten years		395,910		403,353
	$	565,109	$	575,003

Schedule of Unrealized Loss on Investments [Table Text Block]

	In Thousands, Except Number of Securities
	Less than 12 Months						12 Months or More						Total
September 30, 2020	Fair Value		Unrealized Losses		Number of Securities Included		Fair Value		Unrealized Losses		Number of Securities Included		Fair Value		Unrealized Losses
Available-for-Sale Securities:
GSEs	$	37,470	$	78		14	$	—	$	—		—	$	37,470	$	78
Mortgage-backed securities		66,980		586		23		2,096		21		11		69,076		607
Asset-backed securities		564		6		1		8,792		127		1		9,356		133
Corporate bonds		—		—		—		—		—		—		—		—
Obligations of states and political subdivisions		30,180		335		18		697		18		1		30,877		353
	$	135,194	$	1,005		56	$	11,585	$	166		13	$	146,779	$	1,171

	In Thousands, Except Number of Securities
	Less than 12 Months						12 Months or More						Total
December 31, 2019	Fair Value		Unrealized Losses		Number of Securities Included		Fair Value		Unrealized Losses		Number of Securities Included		Fair Value		Unrealized Losses
Available-for-Sale Securities:
GSEs	$	16,507	$	114		5	$	24,658	$	90		9	$	41,165	$	204
Mortgage-backed securities		45,862		182		21		56,917		453		52		102,779		635
Asset-backed securities		17,807		161		10		7,317		142		4		25,124		303
Corporate bonds		—		—		—		—		—		—		—		—
Obligations of states and political subdivisions		30,423		783		26		3,858		45		10		34,281		828
	$	110,599	$	1,240		62	$	92,750	$	730		75	$	203,349	$	1,970