CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Allowances on accounts receivable	$ 170,263	$ 191,285
Accumulated depreciation	$ 18,200,935	$ 17,947,675
Series A Redeemable convertible preferred stock, par value	$ 0.001	$ 0.001
Series A Redeemable convertible preferred stock, shares authorized	2,000,000	2,000,000
Series A Redeemable convertible preferred stock, shares issued	900,000	900,000
Series A Redeemable convertible preferred stock, shares outstanding	900,000	900,000
Series A Redeemable convertible preferred stock, redemption value	$ 9,000,000	$ 9,000,000
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	57,805,087	57,194,817
Common stock, shares outstanding	42,277,017	41,666,747
Common Stock held in treasury, shares	15,528,070	15,528,070

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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