Note 3 - Revenue Recognition (Details Textual) $ in Thousands	3 Months Ended			6 Months Ended		12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021 USD ($)	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Revenue Benchmark [Member] | Customer Concentration Risk [Member]
Number of Customers	1		1	1	1
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | One Customer [Member]
Concentration Risk, Percentage	61.00%		61.00%	64.00%	62.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member]
Number of Customers				2		2
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Two Customers [Member]
Concentration Risk, Percentage				48.00%		69.00%
Contract Assets [Member] | Customer Concentration Risk [Member]
Number of Customers				2		2
Revision of Prior Period, Adjustment [Member] | Revenue Reclassified From Legacy OEM to Value Based ITEC [Member] | Legacy OEM [Member]
Revenue from Contract with Customer, Including Assessed Tax		$ (682)
Revision of Prior Period, Adjustment [Member] | Revenue Reclassified From Legacy OEM to Value Based ITEC [Member] | Hearing Health Value Based ITEC [Member]
Revenue from Contract with Customer, Including Assessed Tax		$ 682