Note 3 - Securities (Details) - Securities Available-for-sale - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	$ 240,234	$ 225,279
Securities available-for-sale, gross unrealized gains	1,202	2,148
Securities available-for-sale, gross unrealized losses	5,305	4,583
Securities available-for-sale, fair value	236,131	222,844
US Government Agencies Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	216,897	197,740
Securities available-for-sale, gross unrealized gains	519	973
Securities available-for-sale, gross unrealized losses	4,952	4,494
Securities available-for-sale, fair value	212,464	194,219
US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	15,934	18,529
Securities available-for-sale, gross unrealized gains	541	851
Securities available-for-sale, gross unrealized losses	0	0
Securities available-for-sale, fair value	16,475	19,380
Collateralized Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	1,199	1,830
Securities available-for-sale, gross unrealized gains	120	184
Securities available-for-sale, gross unrealized losses	0	0
Securities available-for-sale, fair value	1,319	2,014
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	6,015	6,991
Securities available-for-sale, gross unrealized gains	22	140
Securities available-for-sale, gross unrealized losses	291	27
Securities available-for-sale, fair value	5,746	7,104
Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	189	189
Securities available-for-sale, gross unrealized gains	0	0
Securities available-for-sale, gross unrealized losses	62	62
Securities available-for-sale, fair value	$ 127	$ 127

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=51813488&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=27724398&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=49167202&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
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-Topic 320
-SubTopic 10
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-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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Amount before tax of unrealized loss 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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-Paragraph 2
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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
-Subparagraph (SX 210.5-02.2)
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