Note 10 - Income Taxes (Details Textual) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Unrecognized Tax Benefits	$ 0	$ 0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	0	0
Liability for Uncertainty in Income Taxes, Current	0	0
Unrecognized Tax Benefits, Income Tax Penalties Expense	0	0
Unrecognized Tax Benefits, Interest on Income Taxes Expense	$ 0	$ 0

Amount recognized for uncertainty in income taxes classified as current.

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 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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Amount of expense for penalties related to a tax position claimed or expected to be claimed in the tax return.

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- Definition

Amount of interest expense for an underpayment of income taxes.

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