Note 1 - Description of Business and Summary of Significant Accounting Policies - Potentially Dilutive Shares Excluded From Calculation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share-Based Payment Arrangement, Option [Member]
Potentially dilutive securities (in shares)	1,248,513	384,444	1,158,220	317,909
Equity Awards [Member]
Potentially dilutive securities (in shares)	76,036	35,275	36,826	68,341

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration