Note 8 - Commitments and Contingencies (Details Textual) - USD ($) $ in Thousands  | 
Mar. 31, 2024  | 
Sep. 08, 2017  | 
|---|---|---|
| XOMA Ltd. [Member] | Maximum [Member] | ||
| Indefinite-Lived License Agreements | $ 14,925 | |
| Onxeo [Member] | ||
| License Agreement Fee | $ 1,000 | 
| X | ||||||||||
- Definition Amount of license agreement fee paid. No definition available. 
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| X | ||||||||||
- Definition Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the capitalized costs to acquire rights under a license arrangement (for example, to sell specified products in a specified territory) having an indefinite period of benefit. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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| X | ||||||||||
- Details 
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| X | ||||||||||
- Details 
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| X | ||||||||||
- Details 
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