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Stock Options Table FV of Options (Details) (USD $)	3 Months Ended		9 Months Ended
Stock Options Table FV of Options (Details) (USD $)	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Risk free interest rate	0.60%	1.50%	0.90%	2.00%
Expected option lives	5 years	5 years	5 years	5 years
Expected volatility	107.80%	116.10%	111.00%	117.30%
Estimated forfeiture rate	10.00%	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	$ 1.51	$ 1.67	$ 2.30	$ 1.84

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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