Note 1 - General - Sales as Percentage of the Company's Total Revenue by Major Customers (Details) - Customer Concentration Risk [Member] - Sales Revenue, Net [Member]		12 Months Ended
		Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
VTech Holdings Ltd [Member]
Major Customers/ Distributors		24.00%		27.00%		29.00%
Nexty Electronics Corporation [Member]
Major Customers/ Distributors	[1],[2]	11.00%		12.00%		12.00%
Ascend Technology Inc [Member]
Major Customers/ Distributors	[1],[3]	26.00%		23.00%		16.00%
Samsung Mobile [Member]
Major Customers/ Distributors			[4]		[4]	12.00%

[1] Distributor

[2] Nexty Electronics sells the Company’s products to a limited number of customers. One customer, Panasonic Communications Co., Ltd. (“Panasonic”) has continually accounted for a majority of the sales of Nexty Electronics. Sales to Panasonic through Nexty Electronics generated approximately 9%, 10% and 10% of the Company’s total revenues for 2018, 2017 and 2016, respectively.

[3] Ascend Technology sells the Company’s products to a limited number of customers; however none of those customers accounted for more than 10% of the Company’s total revenues for 2018, 2017 and 2016.

[4] Less than 10%.