Note 10 - Marketable Securities - Net Gains and Losses on Marketable Securities (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Net gains recognized during the period on marketable securities	$ 24,576	$ (9,501)	$ 36,926	$ 31,995
Less: Net losses realized on marketable securities sold during the period	0	0	1,507	0
Net unrealized gains recognized during the reporting period on marketable securities still held at the reporting date	$ 24,576	$ (9,501)	$ 38,433	$ 31,995