Note 7 - EMPLOYEE BENEFIT PLANS - Allocation of Recognized Period Costs (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Stock-based compensation expenses	$ 5,553	$ 3,369
Cost of Sales [Member]
Stock-based compensation expenses	728	652
Research and Development Expense [Member]
Stock-based compensation expenses	3,168	1,588
Selling, General and Administrative Expenses [Member]
Stock-based compensation expenses	$ 1,657	$ 1,129

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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