Note 4 - Right-of-use (ROU) Asset (Details Textual)	Jun. 30, 2021 USD ($)
Office Lease Obligations Beyond One Year	$ 83,000
Accrued Liabilities, Current and Noncurrent [Member]
Operating Lease, Liability, Total	$ 171,000

Present value of lessee's discounted obligation for lease payments from operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

Name:	us-gaap_OperatingLeaseLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant