Note 10 - Commitments and Contingencies - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Current lease cost	$ 8	$ 321	$ 51	$ 642
Long-term lease cost	256	194	835	387
Total operating lease cost	264	515	886	1,029
Amortization of right-of-use assets	25	76	145	144
Interest on lease liabilities	2	8	14	17
Total lease cost	$ 27	$ 84	$ 159	$ 161
Weighted-average lease term (years), operating (Year)	4 years 94 days	4 years 310 days	4 years 94 days	4 years 310 days
Weighted-average discount rate, operating	6.08%	6.08%	6.08%	6.08%
Weighted-average lease term (years), financing (Year)	2 years 94 days	2 years 149 days	2 years 94 days	2 years 149 days
Weighted-average discount rate, financing	5.95%	6.10%	5.95%	6.10%

Amount of long-term lease cost, excluding expense for lease with term of one month or less.

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- Definition

Amount of interest expense on finance lease liability.

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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

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

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- Definition

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

+ References

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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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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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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