Note 4 - Leases, Right-to-use Assets and Related Liabilities - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Financing lease cost	$ 1
Operating lease cost	471	345
Short-Term lease cost	13	17
Variable lease cost	32	33
Total lease cost	517	395
Operating cash flows from finance lease	1
Operating cash flows from operating leases	471	345
Right-of-use asset purchased with financing lease	$ 13
Weighted-average remaining lease term, financing lease (months) (Month)	4 years 330 days
Weighted-average remaining lease term, operating leases (months) (Month)	1 year 180 days	1 year 240 days
Weighted-average discount rate - financing lease	21.00%
Weighted-average discount rate - operating leases	12.00%	12.00%

Amount of interest expense on finance lease liability.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount of interest paid on finance lease liability.

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

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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.

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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.

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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.

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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 increase in right-of-use asset obtained in exchange for finance lease liability.

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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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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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