Note 9 - Income Taxes - Unrecognized Tax Benefits Activity (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Balance	$ 2,394	$ 995	$ 1,060
Increases related to prior year tax positions		1,737	246
Decreases related to prior year positions	0	0	0
Increases related to current year tax positions			42
Decreases related to settlements with taxing authorities	(88)	(182)	(126)
Decreases related to lapsing of statute of limitations	(255)	(156)	(227)
Balance	$ 2,051	$ 2,394	$ 995

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=65882285&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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