Note 4 - Investment Securities (Tables)

12 Months Ended

Dec. 31, 2017

Notes Tables

Marketable Securities [Table Text Block]

	2017
			Gross		Gross
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
Available for sale
U.S. Treasuries and government agencies	$	3,000	$	--	$	(37	)	$	2,963
Municipal securities		92,057		1,013		(125	)		92,945
Residential mortgage-backed securities		96,453		338		(1,113	)		95,678
Corporate debt securities		5,000		220		--			5,220
Total available for sale	$	196,510	$	1,571	$	(1,275	)	$	196,806
Held to maturity
Municipal securities	$	42,775	$	388	$	(314	)	$	42,849
Total held to maturity	$	42,775	$	388	$	(314	)	$	42,849

	2016
			Gross		Gross
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
Available for sale
U.S. Treasuries and government agencies	$	5,657	$	5	$	(31	)	$	5,631
Municipal securities		88,276		343		(1,569	)		87,050
Residential mortgage-backed securities		96,870		348		(1,423	)		95,795
Total available for sale	$	190,803	$	696	$	(3,023	)	$	188,476
Held to maturity
Municipal securities	$	26,977	$	16	$	(1,903	)	$	25,090
Total held to maturity	$	26,977	$	16	$	(1,903	)	$	25,090

Schedule of Unrealized Loss on Investments [Table Text Block]

	2017
	Less than 12 Months				12 Months or More				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
U.S. Treasuries and government agencies	$	494	$	6	$	1,969	$	31	$	2,463	$	37
Municipal securities		14,335		55		20,633		384		34,968		439
Residential mortgage-backed securities		31,115		167		40,947		946		72,062		1,113
Total	$	45,944	$	228	$	63,549	$	1,361	$	109,493	$	1,589

	2016
	Less than 12 Months				12 Months or More				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
U.S. Treasuries and government agencies	$	1,969	$	31	$	--	$	--	$	1,969	$	31
Municipal securities		73,194		3,472		--		--		73,194		3,472
Residential mortgage-backed securities		78,725		1,423		--		--		78,725		1,423
Total	$	153,888	$	4,926	$	--	$	--	$	153,888	$	4,926

Investments Classified by Contractual Maturity Date [Table Text Block]

	December 31, 201 7
	Available for Sale							Held to Maturity
					Weighted							Weighted
	Amortized Cost		Fair Value		Average Rate			Amortized Cost		Fair Value		Average Rate
Within one year	$	4,371	$	4,372		2.04	%	$	--	$	--		--
Due from one year to five years		15,925		15,911		2.23	%		--		--		--
Due from five years to ten years		19,145		19,517		3.51	%		6,506		6,548		2.20	%
Due after ten years		60,616		61,328		2.91	%		36,269		36,301		2.80	%
		100,057		101,128		2.88	%		42,775		42,849		2.71	%
Residential mortgage-backed securities		96,453		95,678		2.41	%		--		--		--
Total	$	196,510	$	196,806		2.65	%	$	42,775	$	42,849		2.71	%

Realized Gain (Loss) on Investments [Table Text Block]

	201 7		2016			2015
Sales proceeds	$	2,069	$	30,386		$	21,099
Gross realized gains	$	48	$	195		$	92
Gross realized losses		--		(176	)		(72	)
Net gains on sales of investment securities	$	48	$	19		$	20

Schedule of Other Investment Securities [Table Text Block]

	201 7		201 6
FHLB Stock	$	19,136	$	5,927
FRB Stock		7,610		7,501
Other investments		331		331
Total	$	27,077	$	13,759