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Share-based Compensation Stock Based Plans Valuation Assumptions (Details) (Stock Options [Member])	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Stock Options [Member]
Expected Dividend Yield	0.00%	0.00%
Risk Free Interest Rate	0.77%	0.96%
Expected Option Life	5 years 1 month 16 days	5 years 1 month 16 days
Expected Volatility Factor	99.70%	87.80%

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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