Note 7 -Investment Securities Available-for-sale (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	$ 368,834	$ 361,915
Investment securities available-for-sale, gross unrealized holding gains	5,201	3,554
Investment securities available-for-sale, gross unrealized holding losses	(1,734)	(4,381)
Investment securities available-for-sale, amortized cost	365,367	362,742
US Government Agencies Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	65,812	61,779
Investment securities available-for-sale, gross unrealized holding gains	167	88
Investment securities available-for-sale, gross unrealized holding losses	(98)	(490)
Investment securities available-for-sale, amortized cost	65,743	62,181
US States and Political Subdivisions Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	73,560	78,954
Investment securities available-for-sale, gross unrealized holding gains	1,701	1,554
Investment securities available-for-sale, gross unrealized holding losses	(37)	(31)
Investment securities available-for-sale, amortized cost	71,896	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	132,746	136,681
Investment securities available-for-sale, gross unrealized holding gains	2,277	944
Investment securities available-for-sale, gross unrealized holding losses	(11)	(920)
Investment securities available-for-sale, amortized cost	130,480	136,657
Collateralized Mortgage Obligations [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	79,264	65,610
Investment securities available-for-sale, gross unrealized holding gains	422	178
Investment securities available-for-sale, gross unrealized holding losses	(298)	(1,178)
Investment securities available-for-sale, amortized cost	79,140	66,610
Collateralized Debt Obligations [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	2,275	2,653
Investment securities available-for-sale, gross unrealized holding gains	246	259
Investment securities available-for-sale, gross unrealized holding losses	(950)	(897)
Investment securities available-for-sale, amortized cost	2,979	3,291
Corporate Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	7,112	9,004
Investment securities available-for-sale, gross unrealized holding gains	50	15
Investment securities available-for-sale, gross unrealized holding losses	(8)	(95)
Investment securities available-for-sale, amortized cost	7,070	9,084
Equity Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale	8,065	7,234
Investment securities available-for-sale, gross unrealized holding gains	338	516
Investment securities available-for-sale, gross unrealized holding losses	(332)	(770)
Investment securities available-for-sale, amortized cost	$ 8,059	$ 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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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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+ References

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

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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