Note 6 - Amounts Receivable	3 Months Ended
Mar. 31, 2025
Notes to Financial Statements
Loans, Notes, Trade and Other Receivables Disclosure [Text Block]	6. Amounts Receivable Amounts receivable consisted primarily of accrued interest receivable on marketable securities of $229,000 and $235,000 as of March 31, 2025 and December 31, 2024, respectively.

The entire disclosure for claims held for amounts due to entity, excluding financing receivables. Examples include, but are not limited to, trade accounts receivables, notes receivables, loans receivables. Includes disclosure for allowance for credit losses.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/310-10/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

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