Note 2 - Significant Accounting Policies (Detail) - Fair Value Assumption (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Expected stock volatility	53.64%	51.50%	50.70%
Weighted-average stock volatility	53.64%	51.50%	50.70%
Expected dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate	1.11%	2.00%	2.39%
Expected life (years)	5 years	5 years	5 years
Weighted-average fair value of stock options granted (in Dollars per share)	$ 10.95	$ 8.68	$ 5.80

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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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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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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The range of expected volatilities used and the weighted-average expected volatility for an entity using a valuation technique with different volatilities during the contractual term.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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