Note 4 - Investment Securities Available-for-sale (Details) - Gross Realized Gains and Losses From Sales Of Investment Securities Available For Sale (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Gross Realized Gains and Losses From Sales Of Investment Securities Available For Sale [Abstract]
Realized gains						$ 165	$ 471	$ 10,499
Realized losses						(40)	(161)	(5)
Total investment securities gains, net	$ 40us-gaap_GainLossOnSaleOfSecuritiesNet	$ 85us-gaap_GainLossOnSaleOfSecuritiesNet	$ 23us-gaap_GainLossOnSaleOfSecuritiesNet	$ (44)us-gaap_GainLossOnSaleOfSecuritiesNet	$ 331us-gaap_GainLossOnSaleOfSecuritiesNet	$ 125us-gaap_GainLossOnSaleOfSecuritiesNet	$ 310us-gaap_GainLossOnSaleOfSecuritiesNet	$ 10,494us-gaap_GainLossOnSaleOfSecuritiesNet

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

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- Definition

The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.13(h))

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 13

-Subparagraph h

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.3)

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 3

-Article 7

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