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Note 12 - Stock Incentive and Employee Benefit Plans (Detail) - Fair Value Assumption	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Dividend yield	0.00%	0.00%	0.00%
Expected volatility	82.09%	97.40%	93.70%
Risk-free interest rate	0.73%	0.75%	1.33%
Expected life (years)	2 years 6 months	3 years 6 months	4 years 6 months

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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