Information Concerning Industry Segments And Major Customers (Schedule Of Segment Information) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Sales	$ 119,071,439us-gaap_SalesRevenueNet	$ 131,319,510us-gaap_SalesRevenueNet	$ 104,249,654us-gaap_SalesRevenueNet
Cost of sales	76,912,881us-gaap_CostOfRevenue	86,420,982us-gaap_CostOfRevenue	62,752,763us-gaap_CostOfRevenue
Gross profit	42,158,558us-gaap_GrossProfit	44,898,528us-gaap_GrossProfit	41,496,891us-gaap_GrossProfit
Selling, general and administrative expenses	38,627,801	36,742,869	38,100,773
Impairment		5,849,853us-gaap_GoodwillImpairmentLoss
Restructuring expense	237,838us-gaap_RestructuringCharges	1,149,439us-gaap_RestructuringCharges
Operating income (loss)	3,292,919us-gaap_OperatingIncomeLoss	1,156,367us-gaap_OperatingIncomeLoss	3,396,118us-gaap_OperatingIncomeLoss
Depreciation and amortization	2,482,300	2,184,830	2,133,511
Capital expenditures	5,577,039	2,699,347	2,607,958
Assets	100,286,235us-gaap_Assets	103,532,741us-gaap_Assets	112,534,645us-gaap_Assets
Suttle [Member]
Segment Reporting Information [Line Items]
Sales	67,330,307	54,346,428	45,030,184
Cost of sales	46,338,627	38,534,823	33,056,579
Gross profit	20,991,680	15,811,605	11,973,605
Selling, general and administrative expenses	14,388,765	11,869,268	10,905,357
Restructuring expense		225,962
Operating income (loss)	6,602,915	3,716,375	1,068,248
Depreciation and amortization	1,386,523	1,044,363	1,025,380
Capital expenditures	4,470,636	1,215,394	1,167,495
Assets	38,083,529	30,636,805	26,148,148
Transition Networks [Member]
Segment Reporting Information [Line Items]
Sales	43,173,864	43,856,640	53,842,940
Cost of sales	23,975,363	21,438,115	25,848,307
Gross profit	19,198,501	22,418,525	27,994,633
Selling, general and administrative expenses	21,392,643	21,581,156	24,645,048
Impairment		5,849,853
Restructuring expense	237,838	778,760
Operating income (loss)	(2,431,980)	(5,791,244)	3,349,585
Depreciation and amortization	944,149	969,482	981,080
Capital expenditures	589,362	919,376	412,568
Assets	26,508,137	29,440,438	35,851,189
JDL Technologies [Member]
Segment Reporting Information [Line Items]
Sales	8,567,268	33,116,442	5,376,530
Cost of sales	6,598,891	26,448,044	3,847,877
Gross profit	1,968,377	6,668,398	1,528,653
Selling, general and administrative expenses	2,846,393	3,292,445	2,550,368
Restructuring expense		144,717
Operating income (loss)	(878,016)	3,231,236	(1,021,715)
Depreciation and amortization	151,628	170,985	127,051
Capital expenditures	42,914	46,014	36,891
Assets	3,815,548	11,350,381	8,385,337
Other [Member]
Segment Reporting Information [Line Items]
Capital expenditures	474,127	518,563	991,004
Assets	$ 31,879,021	$ 32,105,117	$ 42,149,971

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.

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