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Note 3 - Securities (Tables)

12 Months Ended

Dec. 31, 2020

Notes Tables

Available-for-sale Securities [Table Text Block]

		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

		December 31, 2019
Available for sale:		Amortized Cost				Gross Unrealized Gains				Gross Unrealized Losses				Fair Value
U.S. Government agencies and corporations		$	119,903			$	1,995			$	775			$	121,123
States and political subdivisions			88,092				791				644				88,239
Mortgage-backed securities			223,173				45				1,435				221,783
Corporate debt securities			3,998				120				-				4,118
Total securities available for sale		$	435,166			$	2,951			$	2,854			$	435,263

Investments Classified by Contractual Maturity Date [Table Text Block]

		December 31, 2020
Available for sale:		Amortized Cost				Fair Value
Due in one year or less		$	4,002			$	4,048
Due after one year through five years			5,605				5,787
Due after five years through ten years			141,804				146,716
Due after ten years			378,664				390,191
Total securities available for sale		$	530,075			$	546,742

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

		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

		December 31, 2019
		Less Than 12 Months								12 Months or More
		Fair Value				Unrealized Loss				Fair Value				Unrealized Loss
U.S. Government agencies and corporations		$	53,244			$	738			$	38,962			$	37
State and political subdivisions			35,934				596				591				48
Mortgage-backed securities			181,279				1,435				-				-
Total temporarily impaired securities		$	270,457			$	2,769			$	39,553			$	85

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

		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

		For the year ended December 31, 2019
		Proceeds				Book Value				Gross Gain				Gross Loss				Net Gain
Available for sale		$	348,032			$	347,466			$	1,157			$	591			$	566

		For the year ended December 31, 2018
		Proceeds				Book Value				Gross Gain				Gross Loss				Net Gain
Available for sale		$	17,287			$	17,270			$	17			$	-			$	17
Held to maturity			6,430				6,430				-				-				-

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27290-111563

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