Note 5 - Accrued Liabilities - Accrued Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Deferred revenue - subscription rental program	$ 617	$ 662
Accrued bonuses	589	726
Accrued payroll and other related expenses	335	839
Accrued professional fees	133	592
Accrued sales commission	20	281
Accrued inventory		474
Accrued interest	6	440
Other accruals	66	255
Total accrued liabilities	1,990	4,698	[1]
Customer Advances [Member]
Contract with customer, liability	21	53
Customer Contracts Liabilites [Member]
Contract with customer, liability		108
Accrued Liabilities [Member]
Current operating lease liabilities	$ 203	$ 268

[1] The condensed consolidated balance sheet as of December 31, 2019 has been derived from the audited consolidated financial statements as of that date.