Note 13 - Stock-based Compensation - Summary of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Payment Arrangement, Expense	$ 2,260	$ 3,090	$ 2,803
Stock Options [Member]
Share-based Payment Arrangement, Expense	174	0	11
Restricted Stock Units and Performance Share Units [Member]
Share-based Payment Arrangement, Expense	$ 2,086	$ 3,090	$ 2,792

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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