6. STOCK-BASED COMPENSATION (Details) (USD $)	3 Months Ended
Mar. 31, 2013
STOCK BASED COMPENSATION
Exercisable at the end	5,481,250
OutstandingOptionsandWarrantsUnderthe2006Planand2000PlanMember
STOCK BASED COMPENSATION
Begining Balance	6,231,250
Granted
Exercised
Canceled or expired	(100,000)
Ending Balance	6,131,250
Exercisable at the end	5,481,250
Weighted Average Exercise price Per Common Share
Begining Balance	$ 3.58
Granted
Exercised
Canceled or expired	$ 9.23
Ending Balance	$ 3.49
Exercisable at the end	$ 3.52
Weighted Average Remaining Contractual Life
Ending Balance	1 year 8 months 1 day
Exercisable at the end	1 year 6 months 15 days
Aggregate Intrinsic Value
Ending Balance	$ 1,392,200
Exercisable at the end	1,292,317
NonPlanOutstandingWarrantsMember
STOCK BASED COMPENSATION
Begining Balance	1,502,898
Granted
Exercised	(1,172,898)
Canceled or expired
Ending Balance	330,000
Exercisable at the end	330,000
Weighted Average Exercise price Per Common Share
Begining Balance	$ 1.50
Granted
Exercised	$ 1.12
Canceled or expired
Ending Balance	$ 2.87
Exercisable at the end	$ 2.87
Weighted Average Remaining Contractual Life
Ending Balance	1 year 10 months 6 days
Exercisable at the end	1 year 10 months 6 days
Aggregate Intrinsic Value
Ending Balance	36,000
Exercisable at the end	$ 36,000

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

+ References

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Gross number of share options (or share units) granted during the period.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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