Segment Reporting (Summary Of Data By Industry Segment) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Revenue, net	$ 30,109	$ 25,363
Income (loss) before income taxes	906	956
Income (loss)		769
Identifiable assets (excluding goodwill)	110,088	48,761
Goodwill	10,808	10,808	$ 10,808
Depreciation and amortization	810	654
Capital expenditures	954	485
Body Worn Devices [Member]
Revenue, net	28,479	23,572
Income (loss) before income taxes	2,388
Income (loss)		1,222
Identifiable assets (excluding goodwill)	105,182	42,121
Goodwill	9,551	9,551
Depreciation and amortization	749	604
Capital expenditures	934	475
Hearing Health DTEC [Member]
Revenue, net	1,630	1,791
Income (loss) before income taxes	(1,482)
Income (loss)		(453)
Identifiable assets (excluding goodwill)	4,906	6,640
Goodwill	1,257	1,257
Depreciation and amortization	61	50
Capital expenditures	$ 20	$ 10

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