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Note 16 - Merger Transaction (Details Textual) - Trigr Therapeutics, Inc. [Member] - USD ($) $ in Millions		3 Months Ended	12 Months Ended
	May 11, 2021	Dec. 31, 2021	Dec. 31, 2021
Stock Issued During Period, Shares, Purchase of Assets (in shares)	10,265,133
Asset Acquisition, Consideration Transferred, Equity Interest Issued and Issuable	$ 50.3
Asset Acquisition, Consideration Transferred, Transaction Cost	0.3		$ 0.3
Asset Acquisition, Consideration Transferred, Total			$ 50.6
Milestone Payment Under the Elpiscience Agreement [Member]
Asset Acquisition, Contingent Consideration, Liability, Total	2.0
Payment for Contingent Consideration Liability, Financing Activities		$ 2.0
Regional License Agreement with Specific Third Party [Member]
Asset Acquisition, Contingent Consideration, Liability, Total	2.0
Filing Biologics License Application in United States [Member]
Asset Acquisition, Contingent Consideration, Liability, Total	5.0
Maximum [Member]
Asset Acquisition, Contingent Consideration, Liability, Total	$ 9.0