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Stock Options Table FV of Options (Details) (USD $)	3 Months Ended		6 Months Ended
Stock Options Table FV of Options (Details) (USD $)	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Risk free interest rate	0.70%		0.90%	2.10%
Expected option lives	5 years		5 years	5 years
Expected volatility	109.70%		111.20%	117.40%
Estimated forfeiture rate	10.00%		10.00%	10.00%
Expected dividend yields	0.00%	0.00%	0.00%	0.00%
Weighted average grant date fair value of options	$ 1.66		$ 2.37	$ 1.87

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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