Note 11 - Stockholders' Equity (Details) - Stock Option Plan (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Note 11 - Stockholders' Equity (Details) - Stock Option Plan [Line Items]
Number of shares, exercised during period	28,000	16,650
Number of shares, ending balance outstanding	259,730
Number of shares, exercisable	147,230
The 1989 Non-Qualified Stock Option Plan [Member]
Note 11 - Stockholders' Equity (Details) - Stock Option Plan [Line Items]
Number of shares, beginning balance outstanding	35,250	41,900
Number of shares, granted during period	0	0
Number of shares, exercised during period	0	6,650
Number of shares, canceled during period	0	0
Number of shares, ending balance outstanding	35,250	35,250
Number of shares, exercisable	35,250	35,250
Weighted average exercise price per share, beginning balance outstanding (in Dollars per share)	$ 4.62	$ 4.82
Weighted average exercise price per share, granted during period (in Dollars per share)	$ 0	$ 0
Weighted average exercise price per share, exercised during period (in Dollars per share)	$ 0	$ 0
Weighted average exercise price per share, canceled during period (in Dollars per share)	$ 0	$ 0
Weighted average exercise price per share, ending balance outstanding (in Dollars per share)	$ 4.62	$ 4.62
Weighted average exercise price per share, exercisable (in Dollars per share)	$ 4.62	$ 4.62
The 2001 Non-Qualified Stock Option Plan [Member]
Note 11 - Stockholders' Equity (Details) - Stock Option Plan [Line Items]
Number of shares, beginning balance outstanding	152,480	162,480
Number of shares, granted during period	0	0	0
Number of shares, exercised during period	28,000	10,000
Number of shares, canceled during period	0	0
Number of shares, ending balance outstanding	124,480	152,480	162,480
Number of shares, exercisable	111,980	127,480
Weighted average exercise price per share, beginning balance outstanding (in Dollars per share)	$ 4.40	$ 4.35
Weighted average exercise price per share, granted during period (in Dollars per share)	$ 0	$ 0
Weighted average exercise price per share, exercised during period (in Dollars per share)	$ 0	$ 0
Weighted average exercise price per share, canceled during period (in Dollars per share)	$ 0	$ 0
Weighted average exercise price per share, ending balance outstanding (in Dollars per share)	$ 4.57	$ 4.40	$ 4.35
Weighted average exercise price per share, exercisable (in Dollars per share)	$ 4.56	$ 4.35
The 2007 Share Incentive Plan [Member]
Note 11 - Stockholders' Equity (Details) - Stock Option Plan [Line Items]
Number of shares, beginning balance outstanding	0	200
Number of shares, granted during period	100,000	0
Number of shares, exercised during period	0	0
Number of shares, canceled during period	0	200
Number of shares, ending balance outstanding	100,000	0
Number of shares, exercisable	0	0
Weighted average exercise price per share, beginning balance outstanding (in Dollars per share)		$ 11.51
Weighted average exercise price per share, ending balance outstanding (in Dollars per share)	$ 11.17

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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