Note 6 - Leases - Summary Analysis of Annual Undiscounted Cash Flows to be Received on Leases (Details) $ in Thousands	Sep. 30, 2023 USD ($)
2024 (excluding the three months ended September 30, 2023)	$ 31
2025	36
Total lease payments	$ 67

Amount of lease payments to be received by lessor for operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479773/842-30-50-12

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of lease payment to be received by lessor for operating lease in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of lease payment to be received by lessor for operating lease in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479773/842-30-50-12

+ Details

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Period Type:	instant