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Note 11 - Stock-Based Compensation (Detail) - Summary of Assumptions Used To Value Options Granted	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Risk–free interest rate	0.27%	2.02%
Expected volatility	39.00%	23.70%
Expected life, in years	2 years 36 days	4 years 292 days
Expected dividend yield	2.91%	3.62%

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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