Note 6 - Accrued Liabilities - Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Accrued payroll and other related expenses	$ 839		$ 877
Accrued bonuses	726		837
Deferred revenue - subscription rental program	662
Accrued professional fees	592		978
Accrued inventory purchases	474
Accrued interest	440		683
Accrued sales commission	281		1,743
Customer contracts liabilities	108		686
Travel and entertainment	78		280
Other accruals	230		682
Accrued liabilities	4,698	$ 6,996	6,766
Accrued Liabilities [Member]
Current operating lease liabilities	$ 268	$ 230