Note 15 - Share-based Payments (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 10,300		$ 10,300
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			2 years 9 months 18 days
Share-based Payment Arrangement, Expense	$ 1,126	$ 1,016	$ 3,357	$ 2,664
Share-based Payment Arrangement, Amount Capitalized			$ 0

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
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Amount of cost capitalized for award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-Publisher FASB
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Amount of cost to be recognized for option under share-based payment arrangement.

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