Note 12 - Income Taxes - Unrecognized Tax Benefits Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Balance	$ 14,431	$ 12,093	$ 16,406
Increase for tax position of current year	2,360	2,095	1,964
Decrease related to settlement with tax authorities			(4,162)
Decrease due to lapse of statue of limitation	(688)		(669)
Decrease for tax position of prior year			(1,446)
Increase for tax position of prior year	169	243
Balance	$ 16,272	$ 14,431	$ 12,093

Amount of unrecognized tax benefits.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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