Note 10 - Leases - Lease Information (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Right-of-use operating lease assets, net	$ 730,000	$ 859,000
Non-current lease liability	$ 604,000	$ 761,000
Weighted average remaining lease term (Year)	3 years 146 days	4 years 146 days
Discount rate	22.00%	22.00%
Current Liabilities [Member]
Current lease liability	$ 157,000	$ 118,000

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of lessee's right to use underlying asset under operating lease.

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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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