Quarterly report pursuant to Section 13 or 15(d)

Note 12 - Concentrations (Details Textual)

v3.20.2
Note 12 - Concentrations (Details Textual) - Customer Concentration Risk [Member]
3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2019
Sep. 30, 2020
USD ($)
Sep. 30, 2019
Dec. 31, 2019
Revenue Benchmark [Member] | Domestic Distributor [Member]        
Concentration Risk, Percentage   40.00%    
Revenue Benchmark [Member] | International Distributor [Member]        
Concentration Risk, Percentage     45.00%  
Revenue Benchmark [Member] | One Customer [Member]        
Concentration Risk, Percentage 54.00%   51.00%  
Accounts Receivable [Member]        
Number of Customers   2    
Accounts Receivable [Member] | Domestic Distributor [Member]        
Concentration Risk, Percentage       77.00%
Accounts Receivable [Member] | Two Customers [Member]        
Accounts Receivable, before Allowance for Credit Loss   $ 720,000    
Accounts Receivable [Member] | Milestone China [Member]        
Concentration Risk, Percentage   74.00%    
Accounts Receivable [Member] | Customer One [Member]        
Concentration Risk, Percentage   60.00%    
Accounts Receivable [Member] | Customer Two [Member]        
Concentration Risk, Percentage   14.00%