Note 12 - Share-based Compensation (Details) - Summary of Stock-Settled Stock Appreciation Rights Transactions (Stock Appreciation Rights (SARs) [Member], USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Stock Appreciation Rights (SARs) [Member]
Note 12 - Share-based Compensation (Details) - Summary of Stock-Settled Stock Appreciation Rights Transactions [Line Items]
Outstanding	452,812	352,952
Outstanding, weighted average exercise price	$ 5.76	$ 5.80
Granted	137,382	119,432
Granted, weighted average exercise price	$ 7.36	$ 5.65
Exercised	(68,170)	(19,572)
Exercised, weighted average exercise price	$ 5.85	$ 5.87
Outstanding	522,024	452,812
Outstanding, weighted average exercise price	$ 6.17	$ 5.76

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The weighted average exercise price for non-option equity instruments.

+ References

No definition available.

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- Definition

The weighted average exercise price for non-option equity instruments exercised during period.

+ References

No definition available.

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- Definition

The weighted average exercise price of non-option equity instruments granted during the period.

+ References

No definition available.

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- Definition

Number of non-option equity instruments exercised by participants.

+ References

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- Definition

Net number of non-option equity instruments granted to participants.

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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(ii)

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

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