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Note 12 - Stock-based Compensation (Details Textual) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2023
Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture	$ 5,000	$ 4,000	$ 168,000
Share-Based Payment Arrangement, Employee [Member]
Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture			$ 37,300
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture			1,963
Shares Issued, Price Per Share	$ 19		$ 19
Director [Member]
Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture			$ 116,100
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture			6,731
Shares Issued, Price Per Share	$ 17.25		$ 17.25
The 2023 Equity Compensation Plan [Member]
Share-Based Payment Arrangement, Expense	$ 4,500	$ 4,500	$ 13,600	$ 13,600
The 2023 Equity Compensation Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 18,200		$ 18,200
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			12 months
The 2023 Equity Compensation Plan [Member] \| Executive Officer [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period					2,000
The 2023 Equity Compensation Plan [Member] \| Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Granted					3,000
The 2023 Equity Compensation Plan [Member] \| Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member] \| Share-Based Payment Arrangement, Tranche One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage					33.33%
The 2023 Equity Compensation Plan [Member] \| Executive Officer [Member] \| Restricted Stock Units (RSUs) [Member] \| Share-Based Payment Arrangement, Tranche Two [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage					33.33%