Note 17 - Segment Reporting - Revenue From Operations by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue	$ 434,395	$ 458,728	$ 445,596
Operating Segments [Member]
Revenue	434,395	458,728	445,596
Operating Segments [Member] \| United States Segment [Member]
Revenue	345,708	360,205	350,535
Operating Segments [Member] \| Europe Segment [Member]
Revenue	74,796	82,805	80,889
Operating Segments [Member] \| Japan Segment [Member]
Revenue	$ 13,891	$ 15,718	$ 14,172

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.

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+ Details