Note 4 -Investment Securities Available-for-sale (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	$ 390,475	$ 361,915
Investment securities available-for-sale, gross unrealized holding gains	2,186	3,554
Investment securities available-for-sale, gross unrealized holding losses	(7,879)	(4,381)
Investment securities available-for-sale, amortized cost	396,168	362,742
US Government Agencies Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	76,650	61,779
Investment securities available-for-sale, gross unrealized holding gains	36	88
Investment securities available-for-sale, gross unrealized holding losses	(2,118)	(490)
Investment securities available-for-sale, amortized cost	78,732	62,181
US States and Political Subdivisions Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	72,295	78,954
Investment securities available-for-sale, gross unrealized holding gains	614	1,554
Investment securities available-for-sale, gross unrealized holding losses	(398)	(31)
Investment securities available-for-sale, amortized cost	72,079	77,431
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	145,301	136,681
Investment securities available-for-sale, gross unrealized holding gains	561	944
Investment securities available-for-sale, gross unrealized holding losses	(2,241)	(920)
Investment securities available-for-sale, amortized cost	146,981	136,657
Collateralized Mortgage Obligations [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	77,415	65,610
Investment securities available-for-sale, gross unrealized holding gains	109	178
Investment securities available-for-sale, gross unrealized holding losses	(1,846)	(1,178)
Investment securities available-for-sale, amortized cost	79,152	66,610
Collateralized Debt Obligations [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	2,281	2,653
Investment securities available-for-sale, gross unrealized holding gains	263	259
Investment securities available-for-sale, gross unrealized holding losses	(891)	(897)
Investment securities available-for-sale, amortized cost	2,909	3,291
Corporate Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	8,030	9,004
Investment securities available-for-sale, gross unrealized holding gains	16	15
Investment securities available-for-sale, gross unrealized holding losses	(57)	(95)
Investment securities available-for-sale, amortized cost	8,071	9,084
Equity Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	8,503	7,234
Investment securities available-for-sale, gross unrealized holding gains	587	516
Investment securities available-for-sale, gross unrealized holding losses	(328)	(770)
Investment securities available-for-sale, amortized cost	$ 8,244	$ 7,488

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
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