XML 32 R77.htm IDEA: XBRL DOCUMENT

Note 16 - Stock-Based and Employee Savings Plans Fair Value Calculation Assumptions (Details)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Valuation Assumptions
Risk-free interest rates	0.70%	1.20%	1.40%
Expected lives (in years)	4 years	3 years 9 months 18 days	3 years 4 months 24 days
Dividend yield	0.00%	0.00%	0.00%
Expected volatility	38.00%	38.00%	37.00%

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.

+ References+ Details