Note 8 - Commitments and Contingencies - Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Operating lease cost	$ 264	$ 312
Sublease income	(158)	(158)
Net lease cost	106	154
Operational cash flow used for operating leases	$ 296	$ 324
Weighted-average remaining lease term (in years) (Year)	1 year 182 days	2 years 73 days
Weighted-average discount rate	12.00%	12.00%

Amount of lease cost recognized by lessee for lease contract.

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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

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

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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 sublease income excluding finance and operating lease expense.

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