Note 5 - Stock-based Compensation - Summary of Restricted Stock Units (Details) - USD ($)	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Share-Based Payment Arrangement, Expense	$ 473,000	$ 160,000
Restricted Stock Units (RSUs) [Member]
Balance (in shares)	479,998
Share-Based Payment Arrangement, Expense	$ 473,000	160,000
Balance (in dollars per share)	$ 12.59
Canceled and forefeited (in shares)	(2,693)
Canceled and forefeited (in dollars per share)	$ 12.81
Balance (in shares)	477,305
Balance (in dollars per share)	$ 12.58
Restricted Stock Units (RSUs) [Member] \| General and Administrative Expense [Member]
Share-Based Payment Arrangement, Expense	$ 38,000	$ 160,000
Restricted Stock Units (RSUs) [Member] \| Research and Development Expense [Member]
Share-Based Payment Arrangement, Expense	$ 435,000

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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