Note 6 - Stock-Based Compensation (Details) - Fair Value of Each Stock Option Grant (USD $)	1 Months Ended	9 Months Ended	12 Months Ended
Jan. 31, 2013	Sep. 30, 2013	Dec. 31, 2012	Dec. 31, 2011
Note 6 - Stock-Based Compensation (Details) - Fair Value of Each Stock Option Grant [Line Items]
Expected Volatility		34.12%	36.64%
Weighted-Average Volatility		34.12%	36.64%	35.60%
Expected Dividends		0.00%	0.00%	0.00%
Expected Term (In years)	10 years	7 years 6 months	7 years 6 months
Risk-Free Rate		1.31%	1.13%	1.82%
Weighted-Average Fair Value (Grant date) (in Dollars per share)		$ 7.83	$ 6.35	$ 4.61
Minimum [Member]
Note 6 - Stock-Based Compensation (Details) - Fair Value of Each Stock Option Grant [Line Items]
Expected Volatility				33.61%
Expected Term (In years)				6 years
Maximum [Member]
Note 6 - Stock-Based Compensation (Details) - Fair Value of Each Stock Option Grant [Line Items]
Expected Volatility				36.64%
Expected Term (In years)				7 years 6 months

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(iii)

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-Name Accounting Standards Codification

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(ii)

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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- Definition

Weighted average expected volatility rate of share-based compensation awards.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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