Note 3 - Securities (Tables)

12 Months Ended

Dec. 31, 2018

Notes Tables

Available-for-sale Securities [Table Text Block]

	December 31, 2018
Available for sale:	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Government agencies and corporations	$	306,264	$	449	$	6,666	$	300,047
States and political subdivisions		118,564		1,218		1,166		118,616
Mortgage-backed securities		586		42		---		628
Corporate debt securities		6,014		---		295		5,719
Total securities available for sale	$	431,428	$	1,709	$	8,127	$	425,010

	December 31, 2017
Available for sale:	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Government agencies and corporations	$	312,604	$	609	$	5,494	$	307,719
States and political subdivisions		16,853		100		119		16,834
Mortgage-backed securities		602		57		---		659
Corporate debt securities		6,016		188		29		6,175
Total securities available for sale	$	336,075	$	954	$	5,642	$	331,387

Investments Classified by Contractual Maturity Date [Table Text Block]

	December 31, 20 1 8
Available for sale:	Amortized Cost		Fair Value
Due in one year or less	$	71,303	$	71,013
Due after one year through five years		181,186		177,141
Due after five years through ten years		85,379		84,584
Due after ten years		93,560		92,272
Total securities available for sale	$	431,428	$	425,010

Debt Securities, Held-to-maturity [Table Text Block]

	December 31, 20 1 7
Held to maturity:	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Government agencies and corporations	$	3,934	$	167	$	---	$	4,101
States and political subdivisions		122,039		2,929		173		124,795
Mortgage-backed securities		209		21		---		230
Corporate debt securities		982		5		---		987
Total securities held to maturity	$	127,164	$	3,122	$	173	$	130,113

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

	December 31, 2018
	Less Than 12 Months				12 Months or More
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
U. S. Government agencies and corporations	$	17,730	$	216	$	259,992	$	6,450
State and political subdivisions		16,882		352		20,758		814
Corporate debt securities		4,842		194		876		101
Total temporarily impaired securities	$	39,454	$	762	$	281,626	$	7,365

	December 31, 2017
	Less Than 12 Months				12 Months or More
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
U. S. Government agencies and corporations	$	68,380	$	871	$	225,738	$	4,623
State and political subdivisions		18,688		194		2,989		98
Corporate debt securities		---		---		948		29
Total temporarily impaired securities	$	87,068	$	1,065	$	229,675	$	4,750

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

	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		---		---		---

	For the year ended December 31, 2017
	Proceeds		Book Value		Gross Gain		Gross Loss		Net Gain
Available for sale	$	13,620	$	13,614	$	10	$	---	$	10
Held to maturity		8,975		8,971		4		---		4

	For the year ended December 31, 201 6
	Proceeds		Book Value		Gross Gain		Gross Loss		Net Gain
Available for sale	$	220,520	$	220,334	$	186	$	---	$	186
Held to maturity		16,160		16,114		46		---		46