Note 11 - Employee Benefits (Details) - Nonvested Option Awards Activity (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Note 11 - Employee Benefits (Details) - Nonvested Option Awards Activity [Line Items]
Granted	76,000
Granted	$ 6.25	$ 5.46	$ 4.81
Forfeited	(24,700)
Service Based Options [Member]
Note 11 - Employee Benefits (Details) - Nonvested Option Awards Activity [Line Items]
Nonvested	282,550	331,450
Nonvested	$ 5.60	$ 5.30
Nonvested	5 years 109 days	5 years 6 months
Granted	76,000
Granted	$ 6.25
Granted	6 years 146 days
Vested	(101,100)
Vested	$ 5.36
Vested	3 years 292 days
Forfeited	(23,800)
Forfeited	$ 4.57
Forfeited	4 years 292 days

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Weighted average remaining contractual term for forfeited options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Weighted average remaining contractual term for options granted, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Weighted average remaining contractual term for nonvested options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Weighted average remaining contractual term for options which vested, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

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.

+ 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 (c)(1)(iv)(3)

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

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- Definition

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

+ References

No definition available.

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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

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

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

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- Definition

Number of non-vested options outstanding.

+ References

No definition available.

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- Definition

Weighted average grant-date fair value of non-vested options forfeited.

+ References

No definition available.

+ Details

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

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- Definition

Number of options vested.

+ References

No definition available.

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- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

+ Details

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