Note 2 - Securities (Tables)

3 Months Ended

Mar. 31, 2016

Investments, Debt and Equity Securities [Abstract]

Available-for-sale Securities [Table Text Block]

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
March 31, 2016
U.S. Government agency debt obligations	$	141,400,000	$	2,076,000	$	(580,000	)	$	142,896,000
Mortgage-backed securities		61,744,000		828,000		(111,000	)		62,461,000
Municipal general obligation bonds		125,794,000		1,948,000		(148,000	)		127,594,000
Municipal revenue bonds		8,798,000		87,000		0			8,885,000
Other investments		1,954,000		15,000		0			1,969,000
	$	339,690,000	$	4,954,000	$	(839,000	)	$	343,805,000
December 31, 2015
U.S. Government agency debt obligations	$	146,660,000	$	1,932,000	$	(1,552,000	)	$	147,040,000
Mortgage-backed securities		66,670,000		708,000		(304,000	)		67,074,000
Municipal general obligation bonds		120,679,000		1,549,000		(205,000	)		122,023,000
Municipal revenue bonds		8,841,000		76,000		(3,000	)		8,914,000
Other investments		1,946,000		0		(5,000	)		1,941,000
	$	344,796,000	$	4,265,000	$	(2,069,000	)	$	346,992,000

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

	Less than 12 Months				12 Months or More				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Loss		Value		Loss		Value		Loss
March 31, 2016
U.S. Government agency debt obligations	$	7,046,000	$	114,000	$	42,601,000	$	466,000	$	49,647,000	$	580,000
Mortgage-backed securities		7,942,000		36,000		17,055,000		75,000		24,997,000		111,000
Municipal general obligation bonds		3,054,000		22,000		10,551,000		126,000		13,605,000		148,000
Municipal revenue bonds		0		0		121,000	< 1,000			121,000	< 1,000
Other investments		0		0		0		0		0		0
	$	18,042,000	$	172,000	$	70,328,000	$	667,000	$	88,370,000	$	839,000

	Less than 12 Months				12 Months or More				Total
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
December 31, 2015
U.S. Government agency debt obligations	$	0	$	0	$	76,496,000	$	1,552,000	$	76,496,000	$	1,552,000
Mortgage-backed securities		18,025,000		69,000		34,660,000		235,000		52,685,000		304,000
Municipal general obligation bonds		1,981,000		4,000		30,134,000		201,000		32,115,000		205,000
Municipal revenue bonds		0		0		1,134,000		3,000		1,134,000		3,000
Other investments		1,446,000		5,000		0		0		1,446,000		5,000
	$	21,452,000	$	78,000	$	142,424,000	$	1,991,000	$	163,876,000	$	2,069,000

Investments Classified by Contractual Maturity Date [Table Text Block]

	Weighted
	Average			Amortized		Fair
	Yield			Cost		Value
Due in 2016		1.47	%	$	36,231,000	$	36,259,000
Due in 2017 through 2021		1.76			122,550,000		123,425,000
Due in 2022 through 2026		3.25			52,425,000		53,629,000
Due in 2027 and beyond		3.48			64,786,000		66,062,000
Mortgage-backed securities		1.77			61,744,000		62,461,000
Other investments		1.53			1,954,000		1,969,000
		2.29	%	$	339,690,000	$	343,805,000