Note 5 - Premises and Equipment, Net (Details) - Summary of Premises and Equipment (USD $)	Mar. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Premises and equipment	$ 72,270,000us-gaap_PropertyPlantAndEquipmentGross	$ 71,962,000us-gaap_PropertyPlantAndEquipmentGross
Less: accumulated depreciation	23,903,000	23,150,000
Premises and equipment, net	48,367,000us-gaap_PropertyPlantAndEquipmentNet	48,812,000us-gaap_PropertyPlantAndEquipmentNet
Land and Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment	16,599,000	16,579,000
Building [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment	38,914,000	38,761,000
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment	$ 16,757,000	$ 16,622,000

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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

-Publisher FASB

-Name Accounting Standards Codification

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

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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

-Publisher FASB

-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

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

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