Note 10 - Commitments - Other Information Related to Operating Leases (Details) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($)
Weighted average remaining lease term in years (Year)	1 year 335 days
Weighted average discount rate	6.75%
Operating cash flows from operating leases	$ 148
Operating cash flows from finance leases
Financing cash flows from finance leases

Amount of interest paid on finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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-Subparagraph (g)(1)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

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Amount of cash outflow for principal payment on finance lease.

+ References

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-Publisher FASB
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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

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

+ References

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