Revenue By Market (Schedule Of Net Revenue By Market)(Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue, Major Customer [Line Items]
Total Revenue	$ 68,009	$ 68,527	$ 67,094
Medical [Member]
Revenue, Major Customer [Line Items]
Total Revenue	37,602	39,609	33,900
Hearing Health [Member]
Revenue, Major Customer [Line Items]
Total Revenue	21,882	21,089	22,959
Hearing Health - Direct To Customer [Member]
Revenue, Major Customer [Line Items]
Total Revenue	1,025
Professional Audio Communications [Member]
Revenue, Major Customer [Line Items]
Total Revenue	$ 7,500	$ 7,829	$ 10,235