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Note 8 - Share-based Compensation - Share-based Compensation Expense (Details) - USD ($)	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
The 2017 Omnibus Incentive Plan [Member]
Allocated Share-based Compensation Expense	$ 218,000	$ 218,000
SEED 2022 Share Incentive Plan [Member]
Allocated Share-based Compensation Expense	26	33
Research and Development Expense [Member] | The 2017 Omnibus Incentive Plan [Member]
Allocated Share-based Compensation Expense	26,000	58,000
Research and Development Expense [Member] | SEED 2022 Share Incentive Plan [Member]
Allocated Share-based Compensation Expense	8	16
General and Administrative Expense [Member] | The 2017 Omnibus Incentive Plan [Member]
Allocated Share-based Compensation Expense	192,000	160,000
General and Administrative Expense [Member] | SEED 2022 Share Incentive Plan [Member]
Allocated Share-based Compensation Expense	$ 18	$ 17

X

- Definition

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

+ References

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
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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