Note 4 - Stock-Based Compensation - Unrecognized Compensation Cost Related to Non-Vested Stock-Based Awards Granted (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Total unrecognized compensation costs	$ 16,051	$ 11,301

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant