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Stock-Based Compensation (Details 4) (USD $)	12 Months Ended
Stock-Based Compensation (Details 4) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Exercise price	$ 2.20	$ 1.14
Expected dividends	0.00%	0.00%
Expected volatility	110.00%	174.00%
Risk free interest rate	0.26%	0.71%
Expected life of warrant	2 years	5 years

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.

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