Note 2 - Summary of Significant Accounting Policies - Concentrations (Details) - Customer Concentration Risk - customer	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue Benchmark
Concentrations
Number of Major Customers	4		3
Concentration Risk, Percentage	78.00%		54.00%
Revenue Benchmark | Customer A
Concentrations
Concentration Risk, Percentage	24.00%		28.00%
Revenue Benchmark | Customer B
Concentrations
Concentration Risk, Percentage	20.00%		14.00%
Revenue Benchmark | Customer C
Concentrations
Concentration Risk, Percentage	20.00%		12.00%
Revenue Benchmark | Customer D
Concentrations
Concentration Risk, Percentage	14.00%
Accounts Receivable.
Concentrations
Number of Major Customers			3
Concentration Risk, Percentage		58.00%	66.00%	49.00%