Note 15 - Fair Value Measurements (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Other Real Estate, Foreclosed Assets, and Repossessed Assets	$ 9,442	$ 20,070
Accounts Receivable Collateral [Member]
Collateral Discount Rates	55.00%
Inventory Collateral [Member]
Collateral Discount Rates	65.00%
Net of Estimated Disposal Costs [Member]
Other Real Estate, Foreclosed Assets, and Repossessed Assets	$ 9,400	$ 20,100
Minimum [Member]
Estimated Sales Cost Applied To Collateral	3.00%
Minimum [Member] \| Warrants Outstanding [Member]
Expected Life Of Warrants	1 year
Fair Value Assumptions, Risk Free Interest Rate	1.83%
Fair Value Assumptions, Expected Volatility Rate	4.70%
Maximum [Member]
Estimated Sales Cost Applied To Collateral	6.00%
Maximum [Member] \| Warrants Outstanding [Member]
Expected Life Of Warrants	6 years
Fair Value Assumptions, Risk Free Interest Rate	2.57%
Fair Value Assumptions, Expected Volatility Rate	12.40%
Core Deposits [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life	4 years
Core Deposits [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life	10 years

No authoritative reference available.

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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