Note 2 - Revenue Recognition - Disaggregation of Revenue By Product and Geography (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenue	$ 233,662	$ 2,785	$ 6,689
Product [Member]
Revenue	92,005	2,633	6,537
Briumvi Ublituximab [Member]
Revenue	92,000
UNITED STATES \| Product [Member]
Revenue	88,786	2,633	6,537
UNITED STATES \| Briumvi Ublituximab [Member] \| Product [Member]
Revenue	88,786
UNITED STATES \| Ukoniq [Member] \| Product [Member]
Revenue		2,633	6,537
International [Member] \| Product [Member]
Revenue	3,219
International [Member] \| Briumvi Ublituximab [Member] \| Product [Member]
Revenue	3,219
Worldwide [Member] \| Product [Member]
Revenue	92,005	2,633	6,537
Worldwide [Member] \| Briumvi Ublituximab [Member] \| Product [Member]
Revenue	$ 92,005
Worldwide [Member] \| Ukoniq [Member] \| Product [Member]
Revenue		$ 2,633	$ 6,537

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 924
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Topic 280
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-4

+ Details