Document and Entity Information [Abstract] Cash Cash Short-term investments Short-term investments Deposits Prepaid Expenses And Other Assets Prepaid expenses and other assets Deposits, prepaid expenses and other assets Land And Building Land and building Land and building Vehicles Vehicles Vehicles Vehicles Property Plant And Equipment Gross Property, Plant and Equipment, Gross, Ending Balance Property, Plant and Equipment, Gross, Beginning Balance Gross property, plant, and equipment, at cost Gross property, plant, and equipment, at cost Property Plant And Equipment Net Total property, plant, and equipment, at cost Total property, plant, and equipment, at cost INTANGIBLE ASSETS, less accumulated amortization INTANGIBLE ASSETS, less accumulated amortization of Parenthetical Value 3 INTANGIBLE ASSETS, less accumulated amortization of $353,202 in 2010 and $325,576 in 2009 Accrued Income Taxes Current Income taxes payable Income taxes payable Common stock, par value $.10 per share; authorized 4,750,000 shares; issued and outstanding 1,974,807 shares in 2010 and 1,967,057 in 2009 Common Stock, Value, Issued, Ending Balance Common Stock, Value, Issued, Beginning Balance Common Stock, Value, Issued, Total Common stock, par value $.10 per share; authorized 4,750,000 shares; issued and outstanding 1,983,587 shares in 2011 and 1,973,357 shares in 2010 Common stock, par value Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common stock Shares Issued Common Stock, Shares, Issued, Total Common stock, shares outstanding Common stock Shares Outstanding Common Stock, Shares, Outstanding, Ending Balance Common Stock, Shares, Outstanding, Beginning Balance Liabilities And Stockholders Equity Total liabilities and stockholders' equity Total liabilities and stockholder's equity Earnings Per Common Share [Abstract] Earnings Per Common Share (EPS) [Abstract] Earnings Per Share Basic Basic Basic Earnings Per Share Diluted Diluted Diluted Weighted Average Number Of Shares Outstanding Basic Basic Basic Weighted Average Number Of Diluted Shares Outstanding Diluted Diluted Loss On Intangible Asset Abandonment Loss on intangible asset abandonment Loss on intangible asset abandonment Cash paid for income taxes, net of refunds received of Parenthetical Value 1 Cash paid for income taxes, net of refunds received of $81,422 and $116,307, respectively Cash paid for income taxes, net of refunds received Short Term Investments [Text Block] Short-Term Investments Short Term Investments Amendment Flag Current Fiscal Year End Date Document Period End Date Document Type Entity Central Index Key Entity Common Stock, Shares Outstanding Entity Current Reporting Status Entity Filer Category Entity Registrant Name Entity Voluntary Filers Entity Well-known Seasoned Issuer Entity Public Float Document Fiscal Period Focus Document Fiscal Year Focus Condensed Balance Sheets [Abstract] Condensed Statements of Operations [Abstract] Condensed Statements of Cash Flows [Abstract] Preferred Stock, Par or Stated Value Per Share Preferred stock, par value Preferred Stock, Shares Authorized Preferred stock, shares authorized Preferred Stock, Shares Issued Preferred Stock, Shares Issued, Total Preferred stock, shares issued Stock-based Compensation [Abstract] Income Taxes [Abstract] Segment Information [Abstract] Segment Reporting. Basis of Presentation [Abstract] Disclosure Of Compensation Related Costs Share Based Payments [Text Block] Stock-based Compensation Preferred Stock, Value, Issued Preferred Stock, Value, Issued, Ending Balance Preferred Stock, Value, Issued, Beginning Balance Preferred Stock, Value, Issued, Total Preferred stock, par value $.10 per share; authorized 250,000 shares; issued none Basis of Presentation [Text Block] Basis of Presentation Segment Information [Text Block] Segment Information Income Taxes [Text Block] Income Taxes ASSETS [Abstract] ASSETS CURRENT ASSETS: [Abstract] CURRENT ASSETS: Trade receivables, less allowance of $68,000 in 2010 and $78,000 in 2009 Accounts Receivable, Net, Current, Total Trade receivables, less allowance of $54,000 in 2011 and $60,000 in 2010 Inventories Inventories Deferred income taxes Deferred income taxes Deferred income taxes Total current assets Total current assets Total current assets PROPERTY, PLANT, AND EQUIPMENT, at cost: [Abstract] PROPERTY, PLANT, AND EQUIPMENT, at cost: Machinery and equipment Machinery and equipment Office equipment Office equipment Less accumulated depreciation Less accumulated depreciation Less accumulated depreciation INTANGIBLE ASSETS, less accumulated amortization of $353,202 in 2010 and $325,576 in 2009 INTANGIBLE ASSETS, less accumulated amortization of $xxx in 2011 and $376983 in 2010 INTANGIBLE ASSETS, less accumulated amortization of $401,941 in 2011 and $376,983 in 2010 Total property, plant, and equipment, at cost Total assets Total property, plant, and equipment, at cost LIABILITIES AND STOCKHOLDERS' EQUITY [Abstract] LIABILITIES AND STOCKHOLDERS' EQUITY CURRENT LIABILITIES: [Abstract] CURRENT LIABILITIES: Accrued compensation Accrued compensation Other accrued expenses Other accrued expenses Total current liabilities Total current liabilities Total current liabilities DEFERRED INCOME TAXES DEFERRED INCOME TAXES DEFERRED INCOME TAXES Total liabilities Total liabilities Total liabilities STOCKHOLDERS' EQUITY: [Abstract] STOCKHOLDERS' EQUITY: Additional paid-in capital Additional paid-in capital Retained earnings Retained earnings Retained earnings Total stockholders' equity Total stockholders' equity Total stockholders' equity NET SALES NET SALES COST OF GOODS SOLD COST OF GOODS SOLD COST OF GOODS SOLD GROSS PROFIT GROSS PROFIT GROSS PROFIT SELLING, GENERAL AND ADMINISTRATIVE EXPENSES SELLING, GENERAL AND ADMINISTRATIVE EXPENSES RESEARCH AND DEVELOPMENT EXPENSES RESEARCH AND DEVELOPMENT EXPENSES RESEARCH AND DEVELOPMENT EXPENSES INCOME FROM OPERATIONS INCOME FROM OPERATIONS INCOME FROM OPERATIONS INTEREST INCOME INTEREST INCOME INTEREST INCOME INCOME BEFORE INCOME TAXES INCOME BEFORE INCOME TAXES INCOME (LOSS) BEFORE INCOME TAXES INCOME TAX EXPENSE INCOME TAX EXPENSE INCOME TAX EXPENSE NET INCOME Net income (loss) NET INCOME Net income WEIGHTED AVERAGE COMMON SHARES OUTSTANDING : [Abstract] WEIGHTED AVERAGE COMMON SHARES OUTSTANDING : CASH FLOWS FROM OPERATING ACTIVITIES: [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES: Adjustments to reconcile net income to net cash provided by operating activities: [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Depreciation Depreciation Amortization Amortization Stock based compensation Stock based compensation (Gain) loss on sale of equipment and vehicles Gain on sale of equipment and vehicles (Gain) loss on sale of equipment and vehicles Changes in working capital components: [Abstract] Changes in working capital components: Trade receivables Trade receivables Trade receivables Inventory Inventory Inventory Deposits, prepaid expenses and other assets Deposits, prepaid expenses and other assets Deposits, prepaid expenses and other assets Accrued expenses Accrued expenses Net cash provided by operating activities Net cash provided by operating activities Net cash provided by operating activities CASH FLOWS FROM INVESTING ACTIVITIES: [Abstract] CASH FLOWS FROM INVESTING ACTIVITIES: Purchases of property, plant and equipment Purchases of property, plant and equipment Purchases of property, plant and equipment Proceeds from sale of equipment and vehicles Proceeds from sale of equipment and vehicles Purchases of intangibles Purchases of intangibles Purchases of intangibles Purchases of short-term investments Purchases of short-term investments Purchases of short-term investments Proceeds on sale of short-term investments Proceeds on sale of short-term investments Net cash used in investing activities Net cash used in investing activities Net cash used in investing activities CASH FLOWS FROM FINANCING ACTIVITIES: [Abstract] CASH FLOWS FROM FINANCING ACTIVITIES: Repurchase of common stock Repurchase of common stock Repurchase of common stock Proceeds from exercise of stock options Proceeds from exercise of stock options Proceeds from exercise of stock options Net cash provided by (used in) financing activities Net cash provided by financing activities Net cash provided by (used in) financing activities NET DECREASE IN CASH NET DECREASE IN CASH NET INCREASE (DECREASE) IN CASH CASH AT BEGINNING OF PERIOD CASH AT END OF PERIOD CASH AT END OF PERIOD CASH AT BEGINNING OF PERIOD CASH AT BEGINNING OF PERIOD SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION [Abstract] SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION Cash paid for income taxes, net of refunds received of $81,422 and $116,307, respectively Cash paid for income taxes, net of refunds received of $xxx and $74156 respectively Cash paid for income taxes, net of refunds received of $4,090 and $81,422, respectively Increase Decrease In Accrued Income Taxes Payable Income taxes payable Income taxes payable Accounts Payable Current Accounts payable Increase Decrease In Accounts Payable Trade Accounts payable Short-Term Investments [Abstract] Inventories [Abstract] Inventory [Text Block] Inventories Earnings Per Common Share (EPS) [Text Block] Earnings Per Common Share (EPS) Trade receivables, less allowance of Parenthetical Value 1 Allowance for Doubtful Accounts Receivable, Current, Ending Balance Allowance for Doubtful Accounts Receivable, Current, Beginning Balance Trade receivables, less allowance