Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Net revenues	$ 41,796us-gaap_Revenues	$ 39,426us-gaap_Revenues
Cost of revenues	21,334us-gaap_CostOfRevenue	20,411us-gaap_CostOfRevenue
Gross margin	20,462us-gaap_GrossProfit	19,015us-gaap_GrossProfit
Operating expenses:
Selling expense	5,735us-gaap_SellingExpense	5,395us-gaap_SellingExpense
Engineering and product development expense	3,580us-gaap_ResearchAndDevelopmentExpense	3,683us-gaap_ResearchAndDevelopmentExpense
General and administrative expense	6,231us-gaap_GeneralAndAdministrativeExpense	5,975us-gaap_GeneralAndAdministrativeExpense
Total operating expenses	15,546us-gaap_OperatingExpenses	15,053us-gaap_OperatingExpenses
Operating income	4,916us-gaap_OperatingIncomeLoss	3,962us-gaap_OperatingIncomeLoss
Other income (expense)	(7)us-gaap_OtherNonoperatingIncomeExpense	46us-gaap_OtherNonoperatingIncomeExpense
Earnings before income tax expense	4,909	4,008
Income tax expense	1,470us-gaap_IncomeTaxExpenseBenefit	931us-gaap_IncomeTaxExpenseBenefit
Net earnings	$ 3,439us-gaap_NetIncomeLoss	$ 3,077us-gaap_NetIncomeLoss
Net earnings per common share:
- Basic (in Dollars per share)	$ 0.33us-gaap_EarningsPerShareBasic	$ 0.30us-gaap_EarningsPerShareBasic
- Diluted (in Dollars per share)	$ 0.33us-gaap_EarningsPerShareDiluted	$ 0.30us-gaap_EarningsPerShareDiluted
Weighted average common shares outstanding:
- Basic (in Shares)	10,431,743	10,363,678
- Diluted (in Shares)	10,466,064	10,419,103

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