Revenue By Market (Schedule Of Net Revenue By Market) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020		Dec. 31, 2019	Dec. 31, 2018
Revenue, Major Customer [Line Items]
Total Net Revenue	$ 102,773	[1]	$ 113,493	$ 113,948
Products And Services Transferred At Point In Time [Member]
Revenue, Major Customer [Line Items]
Total Net Revenue	37,774	[1]	31,400	38,303
Products And Services Transferred Over Time [Member]
Revenue, Major Customer [Line Items]
Total Net Revenue	64,999	[1]	82,093	75,645
Diabetes [Member]
Revenue, Major Customer [Line Items]
Total Net Revenue	59,311		68,606	65,197
Other Medical [Member]
Revenue, Major Customer [Line Items]
Total Net Revenue	19,726		13,487	10,448
Hearing Health Value Based DTEC [Member]
Revenue, Major Customer [Line Items]
Total Net Revenue	4,430		6,120	6,858
Hearing Health Value Based ITEC [Member]
Revenue, Major Customer [Line Items]
Total Net Revenue	5,558		8,910	11,949
Hearing Health Legacy OEM [Member]
Revenue, Major Customer [Line Items]
Total Net Revenue	8,968		9,892	12,257
Professional Audio Communications [Member]
Revenue, Major Customer [Line Items]
Total Net Revenue	$ 4,780		$ 6,478	$ 7,239

[1] During the quarter ended March 31, 2020, we recorded a cumulative adjustment of $1.2 million to reduce revenue within our other medical market to correct an error related to prior periods as a result of our determination that a portion of our sales being recognized over time needed to be recognized at a point in time. The adjustment included a reduction of the related cost of goods sold of $0.8 million and related impacts to reduce the contract asset and an increase to inventory. The adjustment was not material to our Consolidated Financial Statements for any quarterly or annual period.