Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2019	Jul. 01, 2015
Letters of Credit Outstanding, Amount	$ 0
Restricted Cash and Cash Equivalents, Current, Total	309	$ 467
Accounts Receivable, Allowance for Credit Loss, Ending Balance	335	222
Amortization of Intangible Assets, Total	$ 219	$ 219
Preferred Stock, Dividend Rate, Percentage	12.00%
Preferred Stock, Liquidation Preference Per Share	$ 1
Preferred Stock, Dividends Per Share, Declared	$ 0	$ 0
Advertising Expense	$ 101	$ 132
Business Combination, Contingent Consideration, Liability, Total	0	34
Goodwill, Ending Balance	2,375	2,375
Goodwill, Impaired, Accumulated Impairment Loss	908	908
Cumulative Translation Adjustment, Net of Tax, Period Increase (Decrease), Total	(24)
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax, Ending Balance	257	(233)
Foreign Currency Transaction Gain (Loss), before Tax, Total	11	(170)
Operating Lease, Liability, Total	5,224
Operating Lease, Right-of-Use Asset	$ 4,827
Accounting Standards Update 2016-02 [Member]
Operating Lease, Liability, Total			$ 5,731
Operating Lease, Right-of-Use Asset			$ 5,731
Revenue Benchmark [Member] | Product Concentration Risk [Member]
Concentration Risk, Percentage	4.80%	3.10%
Devicix, LLC [Member]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High				$ 2,500