Note 14 - Stock-based Compensation (Details) - Fair Value of Each Option Using Black-Scholes Valuation Model Assumptions	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Note 14 - Stock-based Compensation (Details) - Fair Value of Each Option Using Black-Scholes Valuation Model Assumptions [Line Items]
Risk-free interest rates	1.70%	0.80%	1.00%
Expected life (in years)	5 years 36 days	4 years 219 days	5 years
Dividend yield	0.90%	0.71%	0.81%
Expected volatility	35.10%	37.80%	47.20%
Options to Purchase 300,000 Shares of Common Stock [Member] \| Chief Executive Officer [Member]
Note 14 - Stock-based Compensation (Details) - Fair Value of Each Option Using Black-Scholes Valuation Model Assumptions [Line Items]
Risk-free interest rates	2.36%
Expected life (in years)	7 years 3 months
Dividend yield	0.90%
Expected volatility	42.80%
Forfeiture rate	0.00%
Options to Purchase 100,000 Shares of Common Stock [Member] \| Chief Executive Officer [Member]
Note 14 - Stock-based Compensation (Details) - Fair Value of Each Option Using Black-Scholes Valuation Model Assumptions [Line Items]
Risk-free interest rates	1.64%
Expected life (in years)	4 years 9 months
Dividend yield	0.90%
Expected volatility	33.10%
Forfeiture rate	0.00%

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The fair value assumption of the forfeiture rate.

+ References

No definition available.

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- Definition

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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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- Definition

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

-SubTopic 10

-Section 50

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