Note 11 - Customer and Geographic Information - Revenue Percentage by Major Customers (Details) - Customer Concentration Risk [Member]	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Revenue Benchmark [Member] | Customer A [Member]
Concentration risk	18.00%	22.00%	23.00%	30.00%
Revenue Benchmark [Member] | Customer B [Member]
Concentration risk		16.00%
Revenue Benchmark [Member] | Customer E [Member]
Concentration risk	15.00%
Accounts Receivable [Member] | Customer A [Member]
Concentration risk			11.00%		27.00%
Accounts Receivable [Member] | Customer B [Member]
Concentration risk					14.00%
Accounts Receivable [Member] | Customer C [Member]
Concentration risk			10.00%		12.00%
Accounts Receivable [Member] | Customer D [Member]
Concentration risk			21.00%