Note 2 - Summary of Significant Accounting Policies - Concentrations (Details) - Customer Concentration Risk - customer	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenue Benchmark
Concentrations
Number of Major Customers	4		2
Concentration Risk, Percentage	73.00%		50.00%
Revenue Benchmark | Customer A
Concentrations
Concentration Risk, Percentage	26.00%		33.00%
Revenue Benchmark | Customer B
Concentrations
Concentration Risk, Percentage	16.00%		17.00%
Revenue Benchmark | Customer C
Concentrations
Concentration Risk, Percentage	16.00%
Revenue Benchmark | Customer D
Concentrations
Concentration Risk, Percentage	15.00%
Accounts Receivable.
Concentrations
Number of Major Customers		4	2	4
Concentration Risk, Percentage		55.00%	45.00%	55.00%