Note 8 - Commitments and Contingencies - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Current lease cost	$ 14	$ 291
Long-term lease cost	257	20
Total operating lease cost	271	311
Amortization of right-of-use assets	25	58
Interest on lease liabilities	16	7
Total lease cost	$ 41	$ 65
Weighted-average lease term (years), operating (Year)	3 years 328 days	4 years 127 days
Weighted-average discount rate, operating	6.08%	6.08%
Weighted-average lease term (years), financing (Year)	1 year 332 days	1 year 332 days
Weighted-average discount rate, financing	5.92%	6.10%

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

No definition available.

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- Definition

Amount of interest expense on finance lease liability.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
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- Definition

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

+ References

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- Definition

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

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
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-URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971

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- Definition

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

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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-Topic 842
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- Definition

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

+ References

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