Note 9 - Stock Options & Share-based plan Stock Option Transactions (Details) (USD $)	6 Months Ended
Jun. 30, 2014	Dec. 31, 2013
Number of options
Stock Options
Outstanding	190,400	256,500
Granted	0
Exercised	(9,600)
Forfeited/expired	(56,500)
Exercisable	83,400	120,000
Weighted average Exercise Price
Stock Options
Outstanding	$ 5.26	$ 5.61
Granted	$ 0
Exercised	$ 3.41
Forfeited/expired	$ 7.15
Exercisable	$ 5.90	$ 6.34
Weighted average remaining contractual term (in years)
Stock Options
Outstanding	6.6	5.3
Granted	0
Exercised	0
Forfeited/expired	0
Exercisable	4.9	2.5
Aggregate Intrinsic Value
Stock Options
Outstanding	$ 0	$ 0
Granted	$ 0
Exercised	0
Forfeited/expired	$ 0
Exercisable	$ 118,476	$ 8,850

Weighted Average Contractual Term, Exercisable Shares

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Weighted average contractual term, shares granted during period

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Weighted average remaining contractual term (in years), stock options forfeited/expired

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Weighted average remaining contractual term (in years), stock options exercised

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Weighted average remaining contractual term (years)

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ 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)(i)

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

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 2

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

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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.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The combined weighted average of the accumulated differences between the fair values on underlying shares and exercises prices to acquire such shares as of the grant date on options that were either forfeited or lapsed.

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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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 exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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