Note 14 - Commitments and Contingencies (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Capital Lease Obligations, Total	$ 0	$ 0
Operating Leases, Rent Expense, Net, Total	1,700	1,600	$ 1,700
Accrual for Environmental Loss Contingencies, Ending Balance	0
Indemnification Agreement [Member]
Loss Contingency Accrual, Ending Balance	$ 0	$ 0

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
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-SubTopic 30
-Section 50
-Paragraph 7
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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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- Definition

Amount of loss contingency liability.

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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