Note 10 - Leases (Details Textual) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Operating Lease, Liability, Total	$ 3,867
Operating Lease, Liability, Current	1,000
Operating Lease, Liability, Noncurrent	2,866
Lessee, Operating Lease, Liability, Payments, Due, Total	$ 4,343
Operating Lease, Weighted Average Discount Rate, Percent	5.74%
Operating Lease, Right-of-Use Asset	$ 4,581
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

Amount of lessee's undiscounted obligation for lease payments for operating lease.

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-SubTopic 20
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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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Present value of lessee's discounted obligation for lease payments from operating lease.

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

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

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

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Weighted average discount rate for operating lease calculated at point in time.

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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.

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