Note 11 - Income Taxes (Details) - Unrecognized Tax Benefits Reconciliation - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Unrecognized Tax Benefits Reconciliation [Abstract]
Balance as at January 1, 2013	$ 16,406	$ 14,922	$ 13,081
Balance as of December 31	12,093	16,406	14,922
Increases for tax position of prior year		584	646
Increases for tax position of current year	1,964	1,760	1,528
Decreases related to settlement with tax authorities	(4,162)
Decreases due to lapse of statue of limitations	(669)	$ (860)	$ (333)
Decreases for tax position of prior year	$ (1,446)

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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=6907707&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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Amount of decrease 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 settlements with taxing authorities.

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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.

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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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