Note 1 - Stock Appreciation Rights Activity (Details) - Stock Appreciation Rights (SARs) [Member] - $ / shares	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Outstanding (in shares)	381,566
Outstanding (in dollars per share)	$ 8.14
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted	58,108	53,292
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 16.35
Exercised (in shares)	(36,208)
Exercised (in dollars per share)	$ 5.62
Outstanding (in shares)	403,466
Outstanding (in dollars per share)	$ 9.54

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 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).

+ References

+ Details

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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.

+ References

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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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