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Stockholders' Equity (Details)	3 Months Ended
Stockholders' Equity (Details)	Mar. 31, 2013
Weighted average for key assumptions used in determining the fair value of options granted
Expected price volatility	80.63%
Risk-free interest rate	0.81%
Weighted average expected life in years	6 years
Dividend yield

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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