Note 16 - Segment Information (Details Textual)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Number of Reportable Segments	3
Product Concentration Risk [Member] | Sales Revenue, Segment [Member] | Home [Member] | Smart Home [Member]
Concentration Risk, Percentage	12.00%	14.00%	12.00%
Product Concentration Risk [Member] | Sales Revenue, Segment [Member] | Home [Member] | Telephony [Member]
Concentration Risk, Percentage	45.00%	54.00%	57.00%
Product Concentration Risk [Member] | Sales Revenue, Segment [Member] | Office [Member] | VoIP [Member]
Concentration Risk, Percentage	33.00%	28.00%	19.00%
Product Concentration Risk [Member] | Sales Revenue, Segment [Member] | Mobile [Member]
Concentration Risk, Percentage			12.00%