Note 11 - Share-based Compensation - Share-based Compensation Expense (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Share-based compensation expense	$ 763	$ 765
Basic earnings per share (in dollars per share)	$ 0.05	$ 0.05
Diluted earnings per share (in dollars per share)	$ 0.04	$ 0.05
Cost of Sales [Member]
Share-based compensation expense	$ 74	$ 91
Selling, General and Administrative Expenses [Member]
Share-based compensation expense	$ 689	$ 674

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
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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