Operating Segments - Reconciliation of Segment Financial Data (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Net sales	$ 35,665us-gaap_SalesRevenueNet	$ 31,898us-gaap_SalesRevenueNet
Gross profit	11,181us-gaap_GrossProfit	9,715us-gaap_GrossProfit
Depreciation and amortization	512us-gaap_DepreciationAndAmortization	474us-gaap_DepreciationAndAmortization
Operating income (loss)	1,652us-gaap_OperatingIncomeLoss	249us-gaap_OperatingIncomeLoss
Total assets	24,855us-gaap_Assets	26,459us-gaap_Assets
Electronic Devices [Member]
Total assets	18,817
Communications Equipment [Member]
Total assets	5,763	6,266
Electronic Devices [Member]
Net sales	24,227	21,717
Gross profit	7,489	6,280
Depreciation and amortization	380	288
Operating income (loss)	3,856	2,681
Total assets		20,134
Communications Equipment [Member]
Net sales	11,438	10,181
Gross profit	3,692	3,435
Depreciation and amortization	132	176
Operating income (loss)	25	46
Corporate And Other [Member]
Depreciation and amortization		10
Operating income (loss)	(2,229)	(2,478)
Total assets	$ 275	$ 59

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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