Note 7 - Inventories (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Other Restructuring Costs	$ 0	$ 7,400
Inventory Write-down	0	8,931
Systems [Member]
Inventory Write-down	$ 0	$ 1,500

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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