Note 8 - Goodwill - Changes in the Carrying Value of Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Balance		$ 7,694	$ 7,694	$ 7,851
Effect of foreign currency adjustments			719	(157)
Acquisitions			42,520	0
Impairment	$ (24,400)	$ (18,100)	(42,520)	0	$ 0
Balance	$ 8,413		$ 8,413	$ 7,694	$ 7,851

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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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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