Note 4 - Leases, Right-to-use Assets and Related Liabilities - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Financing lease cost	$ 1		$ 2
Operating lease cost	63	386	534	731
Short-Term lease cost	10	15	23	32
Variable lease cost	40	32	72	65
Total lease cost	$ 114	$ 433	631	828
Operating cash flows from finance lease			2
Operating cash flows from operating leases			534	731
Finance cash flows from finance lease			1
Right-of-use asset purchased with financing lease			$ 13
Weighted-average remaining lease term, financing lease (months) (Month)	4 years 240 days		4 years 240 days
Weighted-average remaining lease term, operating leases (months) (Month)	1 year 30 days	2 years 30 days	1 year 30 days	2 years 30 days
Weighted-average discount rate - financing lease	21.00%		21.00%
Weighted-average discount rate - operating leases	12.00%	12.00%	12.00%	12.00%

Amount of interest expense on finance lease liability.

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Amount of interest paid on finance lease liability.

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Amount of cash outflow for principal payment on finance lease.

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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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