Note 6 - Stockholders' Equity - Share-based Compensation by Award (Details) - $ / shares					6 Months Ended
Dec. 19, 2023	Dec. 16, 2022	Dec. 17, 2021	May 14, 2021	Jun. 30, 2025	Jun. 30, 2024
Options outstanding at beginning of period (in shares)					113,750	119,750
Options outstanding at beginning of period (in dollars per share)					$ 3.27	$ 2.97
Granted (in shares)	19,500	16,500	15,000	70,000	0	0
Granted, weighted average exercise price (in dollars per share)					$ 0	$ 0
Exercised (in shares)					0	0
Exercised, weighted average exercise price (in dollars per share)					$ 0	$ 0
Expired (in shares)					0	(20,000)
Expired, weighted average exercise price (in dollars per share)					$ 0	$ 2.42
Options outstanding (in shares)					113,750	99,750
Options outstanding, weighted average exercise price (in dollars per share)					$ 3.27	$ 3.25
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number (in shares)					113,750	99,750
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price (in dollars per share)					$ 3.27	$ 3.25

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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