Note 6 - Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Operating Lease, Right-of-Use Asset	$ 1,343	$ 1,828
Current portion of operating lease liability	292	702
Operating lease liability, net of current portion	1,134	$ 1,256
Total operating lease liabilities	$ 1,426
Weighted average remaining lease term (years) (Year)	6 years 255 days
Weighted average discount rate	8.40%

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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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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