Note 6 - Goodwill and Intangible Assets - Summary of Changes in the Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Balance	$ 57,935	$ 57,831
Foreign currency translation	34	104
Impairment	(714)	0	$ 0
Balance	$ 57,255	$ 57,935	$ 57,831

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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