Note 13 - Stock-based Compensation - Summary of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Payment Arrangement, Expense	$ 521	$ 523	$ 1,110	$ 1,089
Stock Options [Member]
Share-based Payment Arrangement, Expense	81	50	145	72
Restricted Stock Units and Performance Share Units [Member]
Share-based Payment Arrangement, Expense	$ 440	$ 473	$ 965	$ 1,017

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

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