Note 14 - Share-based Compensation - Stock Appreciation Rights (Details) - $ / shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Outstanding (in dollars per share)	$ 6.09
Stock Appreciation Rights (SARs) [Member]
Outstanding (in shares)	65,250	72,500	76,125
Outstanding (in dollars per share)	$ 9.95	$ 9.95	$ 9.95
Exercised (in shares)	63,250	2,175	1,450
Exercised (in dollars per share)	$ 9.95	$ 9.95	$ 9.95
Canceled or expired (in shares)	2,000	5,075	2,175
Canceled or expired (in dollars per share)	$ 9.95	$ 9.95	$ 9.95
Outstanding (in shares)		65,250	72,500
Outstanding (in dollars per share)		$ 9.95	$ 9.95

Number of non-option equity instruments exercised by participants.

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Number of shares under non-option equity instrument agreements that were either cancelled or expired.

+ References

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=109197908&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=109197908&loc=d3e5070-113901

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- Definition

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

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No definition available.

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

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No definition available.

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Weighted average grant-date fair value of options vested.

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No definition available.

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