Represents number of stockholder approved equity based compensation plans under which stock options have been granted.

No definition available.

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- Definition

Represents the contractual term of stock-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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-Section D

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

No definition available.

+ Details

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- Definition

The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

No definition available.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

No definition available.

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(b)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

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-Publisher FASB

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-Paragraph A240

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

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STOCK-BASED COMPENSATION (Details) (USD $)	12 Months Ended
STOCK-BASED COMPENSATION (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
STOCK-BASED COMPENSATION
Number of stockholder-approved equity-based compensation plans	2
Stock options
Stock-based compensation
Outstanding stock options (in shares)	1,104,859	906,860
Contractual term of stock options	10 years
Stock-based compensation expense	$ 725,625	$ 1,177,683	$ 992,757
Weighted average fair value (in dollars per share)	$ 4.08	$ 7.32	$ 6.66
Weighted average assumptions used in estimation of the fair value of options granted
Expected option life			6 years
Risk-free interest rate, minimum (as a percent)	0.775%	1.175%
Risk-free interest rate, maximum (as a percent)	1.105%	2.57%
Risk-free interest rate (as a percent)			2.42%
Expected stock price volatility, minimum (as a percent)	92.97%	69.07%
Expected stock price volatility, maximum (as a percent)	97.20%	72.16%
Expected stock price volatility (as a percent)			76.05%
Stock options \| Minimum
Stock-based compensation
Vesting period of outstanding stock options	3 years
Weighted average assumptions used in estimation of the fair value of options granted
Expected option life	5 years 6 months	5 years 6 months
Stock options \| Maximum
Stock-based compensation
Vesting period of outstanding stock options	4 years
Weighted average assumptions used in estimation of the fair value of options granted
Expected option life	6 years 3 months	6 years 3 months
2008 Plan \| Stock options
Stock-based compensation
Number of shares of the entity's common stock authorized for issuance under the plan	1,833,333
1998 Plan \| Stock options
Stock-based compensation
Number of shares of the common stock issued	3,416
Outstanding stock options (in shares)	860,828