Note 18 - Segment Reporting - Revenue From Operations by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue	$ 458,728	$ 445,596	$ 344,490
Operating Segments [Member]
Revenue	458,728	445,596	344,490
Operating Segments [Member] \| United States Segment [Member]
Revenue	360,205	350,535	263,086
Operating Segments [Member] \| Europe Segment [Member]
Revenue	82,805	80,889	70,154
Operating Segments [Member] \| Japan Segment [Member]
Revenue	$ 15,718	$ 14,172	$ 11,250

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration