Note 6 - Intellectual Property - Intellectual Property (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets, Gross	$ 69,238	$ 69,238
Finite-Lived Intangible Assets, Accumulated Amortization	(57,399)	(51,902)
Finite-Lived Intangible Assets, Foreign Currency Translation Impact	981	4,931
Intellectual property, net	12,820	22,267
Developed Technology Rights [Member]
Finite-Lived Intangible Assets, Gross	68,838	68,838
Finite-Lived Intangible Assets, Accumulated Amortization	(57,207)	(51,734)
Finite-Lived Intangible Assets, Foreign Currency Translation Impact	947	4,872
Intellectual property, net	12,578	21,976
Technology-Based Intangible Assets [Member]
Finite-Lived Intangible Assets, Gross	400	400
Finite-Lived Intangible Assets, Accumulated Amortization	(192)	(168)
Finite-Lived Intangible Assets, Foreign Currency Translation Impact	34	59
Intellectual property, net	$ 242	$ 291