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Note 3 - Securities (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

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

		December 31, 2021
Available for sale:		Amortized Cost				Gross Unrealized Gains				Gross Unrealized Losses				Fair Value
U.S. Government agencies and corporations		$	279,934			$	2,795			$	4,710			$	278,019
States and political subdivisions			195,365				5,314				2,007				198,672
Mortgage-backed securities			204,164				2,323				313				206,174
Corporate debt securities			3,004				248				37				3,215
Total securities available for sale		$	682,467			$	10,680			$	7,067			$	686,080

		December 31, 2020
Available for sale:		Amortized Cost				Gross Unrealized Gains				Gross Unrealized Losses				Fair Value
U.S. Government agencies and corporations		$	86,859			$	4,477			$	173			$	91,163
States and political subdivisions			196,435				7,778				252				203,961
Mortgage-backed securities			244,780				4,473				78				249,175
Corporate debt securities			2,001				442				-				2,443
Total securities available for sale		$	530,075			$	17,170			$	503			$	546,742

Investments Classified by Contractual Maturity Date [Table Text Block]

		December 31, 2021
Available for sale:		Amortized Cost				Fair Value
Due in one year or less		$	2,519			$	2,540
Due after one year through five years			24,034				24,051
Due after five years through ten years			313,966				313,288
Due after ten years			341,948				346,201
Total securities available for sale		$	682,467			$	686,080

Schedule of Temporary Impairment Losses, Investments [Table Text Block]

		December 31, 2021
		Less Than 12 Months								12 Months or More
		Fair Value				Unrealized Loss				Fair Value				Unrealized Loss
U.S. Government agencies and corporations		$	201,650			$	3,530			$	26,792			$	1,180
State and political subdivisions			50,659				1,214				20,542				793
Mortgage-backed securities			13,139				141				4,665				172
Corporate debt securities			966				37				-				-
Total temporarily impaired securities		$	266,414			$	4,922			$	51,999			$	2,145

		December 31, 2020
		Less Than 12 Months								12 Months or More
		Fair Value				Unrealized Loss				Fair Value				Unrealized Loss
U.S. Government agencies and corporations		$	28,798			$	173			$	-			$	-
State and political subdivisions			32,353				249				635				3
Mortgage-backed securities			8,816				76				4,060				2
Total temporarily impaired securities		$	69,967			$	498			$	4,695			$	5

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

		For the year ended December 31, 2021
		Proceeds				Book Value				Gross Gain				Gross Loss				Net Gain
Available for sale		$	20,377			$	20,371			$	6			$	-			$	6

		For the year ended December 31, 2020
		Proceeds				Book Value				Gross Gain				Gross Loss				Net Gain
Available for sale		$	126,840			$	126,732			$	110			$	2			$	108

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