Note 9 - Subsequent Events	12 Months Ended
Dec. 31, 2021
Notes to Financial Statements
Subsequent Events [Text Block]	9. Subsequent Events In addition to the subsequent events discussed elsewhere in these notes, see below for a discussion of our subsequent events occurring after December 31, 2021. In February 2022, the Company and Exploration Invest Pte Ltd. (Exploration) entered into a license termination agreement pursuant to which the Company agreed to pay Exploration $0.4 million to terminate certain License Agreements and extend its confidentiality requirements until the 10-year anniversary of the license termination agreement. The Company paid $0.4 million to Exploration in February 2022 to satisfy this commitment.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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