Note 1 - The Company and Description of Business (Details Textual) $ in Millions, $ in Millions	Jan. 31, 2023 USD ($)	Jan. 01, 2023 USN ($)
National Institute of Aging Grant [Member]
Government Assistance, Asset	$ 21	$ 21

Amount of asset from government assistance.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 832
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483507/832-10-50-3

Name:	us-gaap_GovernmentAssistanceAmountCumulative
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant