Note 10 - Leases (Details Textual) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Operating Lease, Liability, Total	$ 4,062
Operating Lease, Liability, Current	1,200
Operating Lease, Liability, Noncurrent	2,864
Operating Lease, Right-of-Use Asset	4,716
Operating Lease Right of Use Assets [Member]
Prepaid Rent	$ 700
Minimum [Member]
Lessee, Operating Lease, Term of Contract	1 year
Maximum [Member]
Lessee, Operating Lease, Term of Contract	8 years

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

+ References

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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- Definition

Amount of asset related to consideration paid in advance for rent that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

+ References

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