Note 12 - Share-based Compensation - Summary of Stock-Settled Stock Appreciation Rights Transactions (Details) - Stock Appreciation Rights (SARs) [Member] - $ / shares	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Outstanding SARS (in shares)	381,566	522,024
Outstanding SARS (in dollars per share)	$ 8.14	$ 6.17
Granted SARS (in shares)	58,108	53,292
Granted SARS (in dollars per share)	$ 16.35	$ 18.66
Exercised SARS (in shares)	(114,168)	(193,750)
Exercised SARS (in dollars per share)	$ 6.27	$ 5.73
Outstanding SARS (in shares)	325,506	381,566
Outstanding SARS (in dollars per share)	$ 10.26	$ 8.14

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

No definition available.

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- Definition

The weighted average grant-date fair value of SARS exercised during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Number of non-option equity instruments exercised by participants.

+ References

+ Details

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- Definition

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

+ References

+ Details

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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

+ Details

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- Details

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