Note 13 - Stock-based Compensation - Summary of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Payment Arrangement, Expense	$ 589	$ 566
Stock Options [Member]
Share-based Payment Arrangement, Expense	64	22
Restricted Stock Units and Performance Share Units [Member]
Share-based Payment Arrangement, Expense	$ 525	$ 544

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

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