Note 11 - Concentrations (Details Textual)	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Distributor One [Member]
Concentration Risk, Percentage	13.00%
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Distributor Two [Member]
Concentration Risk, Percentage	13.00%
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Distributor Three [Member]
Concentration Risk, Percentage	31.00%
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Domestic Distributor [Member]
Concentration Risk, Percentage		29.00%
Revenue Benchmark [Member] | Geographic Concentration Risk [Member] | CHINA
Concentration Risk, Percentage		18.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Distributor One [Member]
Concentration Risk, Percentage	12.00%		13.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Distributor Two [Member]
Concentration Risk, Percentage	18.00%		28.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Distributor Three [Member]
Concentration Risk, Percentage	20.00%		29.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Distributor Four [Member]
Concentration Risk, Percentage	21.00%