Note 3 - Stock-based Compensation - Compensation Cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share-based compensation	$ 277	$ 178	$ 694	$ 564
Share-Based Payment Arrangement, Option [Member]
Share-based compensation	20	53	114	275
Stock Unit Awards [Member]
Share-based compensation	$ 257	$ 125	$ 580	$ 289

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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Balance Type:	debit
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