Note 12 - Fair Value Measurements (Details Textual) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Warrants	$ 176,000	$ 91,000
Other Real Estate, Foreclosed Assets, and Repossessed Assets, Total	$ 8,220,000	9,442,000
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, Total	$ 8,200,000	$ 9,400,000
Minimum [Member]
Estimated Sales Cost Applied To Collateral	3.00%
Minimum [Member] \| Measurement Input, Expected Term [Member]
Warrants and Rights Outstanding, Measurement Input	1
Minimum [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Warrants and Rights Outstanding, Measurement Input	2.48
Minimum [Member] \| Measurement Input, Price Volatility [Member]
Warrants and Rights Outstanding, Measurement Input	8.19
Maximum [Member]
Estimated Sales Cost Applied To Collateral	6.00%
Maximum [Member] \| Measurement Input, Expected Term [Member]
Warrants and Rights Outstanding, Measurement Input	6
Maximum [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Warrants and Rights Outstanding, Measurement Input	3.12
Maximum [Member] \| Measurement Input, Price Volatility [Member]
Warrants and Rights Outstanding, Measurement Input	12.8

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- Definition

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Warrants

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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://fasb.org/us-gaap/role/ref/legacyRef
-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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Value of input used to measure outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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