Note 5 - Amounts Receivable	6 Months Ended
Jun. 30, 2023
Notes to Financial Statements
Loans, Notes, Trade and Other Receivables Disclosure [Text Block]	5. Amounts Receivable Amounts receivable consisted primarily of accrued interest receivable on marketable securities of $186,000 and $80,000 as of June 30, 2023 and December 31, 2022, respectively.

The entire disclosure for claims held for amounts due a 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

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