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Stock-Based Compensation (Details)	6 Months Ended
Stock-Based Compensation (Details)	Jun. 30, 2012
Schedule of weighted-average assumptions used to value options as of their grant date
Risk-free interest rate	0.72%
Expected volatility	64.60%
Expected life (in years)	4 years 2 months 19 days
Dividend yield	0.00%

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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