Note 3 - Securities (Tables)

12 Months Ended

Dec. 31, 2017

Notes Tables

Available-for-sale Securities [Table Text Block]

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
201 7
U.S. Government agency debt obligations	$	175,953,000	$	99,000	$	(6,352,000	)	$	169,700,000
M ortgage-backed securities		38,967,000		335,000		(510,000	)		38,792,000
M unicipal general obligation bonds		121,040,000		891,000		(638,000	)		121,293,000
Municipal revenue bonds		3,978,000		30,000		(30,000	)		3,978,000
O ther investments		2,010,000		0		(29,000	)		1,981,000
	$	341,948,000	$	1,355,000	$	(7,559,000	)	$	335,744,000
201 6
U.S. Government agency debt obligations	$	159,271,000	$	106,000	$	(7,337,000	)	$	152,040,000
M ortgage-backed securities		47,329,000		486,000		(423,000	)		47,392,000
M unicipal general obligation bonds		120,284,000		312,000		(1,549,000	)		119,047,000
M unicipal revenue bonds		7,699,000		23,000		(91,000	)		7,631,000
O ther investments		1,979,000		0		(29,000	)		1,950,000
	$	336,562,000	$	927,000	$	(9,429,000	)	$	328,060,000

Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Table Text Block]

	Less than 12 Months				12 Months or More				Total
Description of Securities	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
201 7
U.S. Government agency debt obligations	$	35,677,000	$	434,000	$	115,374,000	$	5,918,000	$	151,051,000	$	6,352,000
Mortgage-backed securities		10,179,000		156,000		21,084,000		354,000		31,263,000		510,000
Municipal general obligation bonds		12,807,000		114,000		54,703,000		524,000		67,510,000		638,000
Municipal revenue bonds		0		0		1,187,000		30,000		1,187,000		30,000
Other investments		1,510,000		29,000		0		0		1,510,000		29,000
	$	60,173,000	$	733,000	$	192,348,000	$	6,826,000	$	252,521,000	$	7,559,000
201 6
U.S. Government agency debt obligations	$	110,160,000	$	7,172,000	$	5,073,000	$	165,000	$	115,233,000	$	7,337,000
Mortgage-backed securities		3,670,000		4,000		37,072,000		419,000		40,742,000		423,000
Municipal general obligation bonds		65,895,000		1,360,000		27,734,000		189,000		93,629,000		1,549,000
Municipal revenue bonds		1,921,000		90,000		206,000		1,000		2,127,000		91,000
Other investments		1,479,000		29,000		0		0		1,479,000		29,000
	$	183,125,000	$	8,655,000	$	70,085,000	$	774,000	$	253,210,000	$	9,429,000

Investments Classified by Contractual Maturity Date [Table Text Block]

	Weighted Average Yield		Amortized Cost		Fair Value
Due in one year or less		1.74%	$	29,667,000	$	29,675,000
Due from one to five years		2.12		65,093,000		64,938,000
Due from five to ten years		2.52		100,128,000		97,943,000
Due after ten years		2.90		106,083,000		102,415,000
Mortgage-backed securities		2.17		38,967,000		38,792,000
Other investments		2.71		2,010,000		1,981,000
		2.46%	$	341,948,000	$	335,744,000